Salomon S Lab NSO Socks – excellent socks for every trail runner from technical trail aficionados to long distance grinders

Salomon socks have been something of an enigma in the US. Although broadly available in Europe, the sock lines have had very limited distribution in the US. This seems to be the result of the fact that Salomon don’t actually own the rights to distribution of their socks- this was sold to Intersock Group (ITA) in 2002 . For a while Interlock Group had a US affiliate in Portland, OR that offered a very limited selection of Salomon socks through a rudimentary online shop and to some retail outlets. This selection included only a few of the running socks. Having been introduced to the full line of excellent Salomon socks whilst in Europe many years ago, I sought out a source here in the US- sometimes the Intersock Group affiliate would have the socks available online but often there was limited stock or certain models were not brought in to the US. So in past years, when in Europe I would pick up a few  pair of socks. It was a non-ideal situation, particularly when the socks started wearing out.

But there seems to be movement on availability of Salomon socks in the US. A new Intersock Group affiliate (Sport Dispatch) has picked up the line and they are bringing in an expanded line of Salomon socks to the US market, including running, alpine, and nordic socks. I was contacted and offered samples for testing and agreed to accept the samples. This post is a review of the S Lab NSO line of Salomon trail running socks- it’s their top-line offering and includes quite a bit of technology. After extensive use of the NSO samples I subsequently purchased six pair of one of the NSO variants, so although I did accept samples, I personally purchased the product because I liked it.

My past use has included three models of Salomon socks, the most recent being a very minimalist sock called the “Sense” sock. It was introduced in 2015 or so and I have been using it since. I bought six pairs and they have only this past season begun wearing out (at the heel counter and in the heel base). That’s four full mountain running seasons of wear and tear and represents excellent durability. The performance was outstanding as the socks provided sufficient protection yet were thin enough to not be intrusive and they dried out very quickly. I had similar experience with prior versions of Salomon socks and have found them to be among the best offerings at any given time.

I am not convinced that a running sock should provide padding and these “Sense” socks provided no padding. I prefer to let my selected shoe provide whatever cushioning I need- the cushioning is where it needs to be and is stable and not potentially moving around or changing fit levels. This is just my preference as I know many runners are convinced that their highly cushioned socks are an important part of their comfort and performance. The following review of the Salomon S Lab NSO socks will be colored by this preference of minimal cushioning.

Salomon S Lab NSO Sock line

Salomon have chosen to divide the S Lab NSO running sock line into three variants- Short Run, Mid Run, and Long Run. The socks have increasing levels of features and technology as the intended use as a function of run length is increased. I’ll review the included technologies and features for each variant but will start with an overview. There is also an NSO compression sock (NSO Leg Up)  that I will mention at the end of this post. The “science” (such that it is) is undecided on the efficacy of compression for recovery and/or support in running and I’ll address that later.

Salomon S Lab NSO 2019 sock line including, Short Run, Mid Run, and Long Run as well as a compression sock called the Leg Up.

nso sock technologies

The “NSO” in the S Lab NSO “Short run”, “Mid run”, “Long run”, and “Leg Up” sock designations refers to the “enso” Zen Buddhist single-stroke calligraphy of a circle. Enso drawings are a part of meditative practice and take many meanings including “harmonious cooperation”, which is the intended meaning put forth by Salomon. More on the “cooperation” aspect below.

Salomon works with their athletes and Intersock Group to design and manufacture the sock lines. This involves interaction of the most demanding users (elite athletes) with the experienced Salomon designers and the sock technology experts at Intersock Group.

The primary new technology offered by the NSO line is based on oxide particle infusion of fabrics. Fabrics with appropriate composition oxide particles are claimed to provide far infrared radiation reflection and emission*. In Salomon’s words- naturally generated heat (including far infrared wavelengths) from the body interacts with the oxide particles in the fabric to “activate and reflect this energy, enhancing muscle tone, recovery, and balance”. Wow, that’s a lot of function from some oxide particles! But let’s back up and look into the proposed basis for this technology.

photobiomodulation (pbm)

Photobiomodulation (PBM) is process in which low levels (fluences) of light energy are utilized to interact in a positive way with human tissue. PBM (also known as Low- Level Laser Therapy (LLLT)) has found utility in treating medical conditions including  hearing loss, foot tendinopathy, diabetes, cardiac conditions, and cancer. PMB is increasingly being accepted as a promising treatment therapy. That, of course, as in any “medical science” claim, does not mean that the therapy is efficacious. It may just mean that a new experimental therapy which has a large placebo effect can be easily made into a profit center. Such is medicine today.

The applications of PBM for athletic endeavor include the use of such treatments to assist in dilation of vascular tissue. Specifically it has been found that nitric oxide synthase (NOS) (an enzyme) participates in numerous biological processes by enabling the in-situ production of NO (nitric oxide) within tissue. NO is claimed to be critical to regulating something called vascular tone. Vascular tone is the degree of constriction of vascular tissue. NO production is associated with vasodilation and therefore promotion of the formation of NO is viewed as being a positive outcome for athletic activity.

NO production is also claimed to be critical to general athletic performance. As usual, the many claims are not well supported (or even supported at all) but you can do your own background reading and decide independently. Beware anything scientific being written by MDs- they are not scientists.

Further, it has also been claimed that NOS production (and therefore NO) is enhanced by radiation of human tissue with far infrared (FIR) wavelengths (about 5 microns-1000 microns (1 mm)). This is a wavelength region situated between mid infrared/near infrared (MIR/NIR) and visible light on the short wavelength end and microwaves on the long wavelength side. Infrared radiation has colloquially been referred to as “heat waves” since this radiation, which is invisible to the human eye, can heat a substance that is comprised of molecules that can oscillate under the influence of the radiation. The molecule movement produces internal friction that results in heat.

For FIR irradiation, water and human tissue are found to be excited by these wavelengths and it is proposed that this excitation can lead to both internal heat generation and enhanced production of NOS and therefore NO. Inference and some observational data indicate that reduced vascular restriction can result from FIR irradiation. FIR, at appropriate intensity, is experienced by the human body as a gentle heat which is a direct result of the interaction of this radiation with human tissue.

OK, so much for NOS and NO (and not to be confused with NSO!…).

Now, it is well known that certain inorganic materials and certain polymers can efficiently reflect and/or emit FIR wavelengths when irradiated with equal or higher energy rays (i.e. FIR wavelengths and shorter). The inorganic materials most prominently used for FIR reflection/emission are primarily mineral oxide compounds such as tourmaline (a naturally occurring borosilicate compound). Fabric manufacturers have been developing products that contain nano-sized particulates of these FIR reflector/emitter compounds. It is asserted that the FIR radiation that naturally emanates from the human body is reflected back into the body and that this can promote increases in NOS and, therefore, NO and, therefore, decreased vascular restriction. Obviously, athletic clothing has been a primary focus for the fabric manufacturers since keeping blood flowing will have only positive effects for both performance and recovery. This proposed effect is also where Salomon have used the “enso” (NSO) connection- the body’s natural generation of FIR is reflected back by the oxide particles and assists in vasodilation via a synergistic, “enso”-like, “harmonious cooperation” process.

There exists scant data that supports any measurable efficacy of the use such FIR reflecting particle-infused clothing in athletic endeavor. There are, however, more reliable, although not conclusive, data for other applications of the use of FIR for treating certain medical conditions (e.g. lymphedema) that have been interpreted as being the result of FIR-induced vasodilation via the NOS-NO pathway. So there is promise but no clarity at the moment on application in athletics.

Lack of data has never stopped marketeers (or “woo-woo” medical practitioners), particularly when what is being marketed involves increased human comfort or, in the case of athletics, increased performance or recovery. And that is where we are today with the use of inorganic particulates in athletic clothing- an essentially made-up advantage (that may or may not end up being real) with manufacturers claiming efficacy and users claiming positive benefits- all without supporting data. Of course we should not ignore the reality of large placebo effects that may be at play as well.

Back to the S Lab NSO socks. What Salomon have done is to include mineral oxide infused fabric in the sock to promote vasodilation in and around the foot and ankle. Feet and ankles, as all runners know, are (and excuse the pun) the Achilles heel of running since all propulsion is centered around the foot and any issue with ones feet (including the Achilles) will very adversely affect ones running. Having strong, high performing, and quickly recovering feet and ankles is critical to being able to train and perform at our best. Salomon are proposing that these socks with FIR reflecting mineral particle infused fabrics will improve our running performance and allow for quicker recovery. Perhaps this is true, but perhaps not, and only further data, analysis, and mechanistic scientific work will give us answers. In the meantime it probably does not hurt to try the technology, make personal observations, and come to some position on the subject. It is claimed that the nano-particles are inhert to the body and serve only to emit/reflect FIR radiation into the body, so there appear to be no downsides to trying these fabrics out. There is, however, the overriding concern about physical absorption of nano-particles into the body and bloodstream and any possible adverse health effects due to absorption of these particles in either short or long term. Something to think about but I’m in the camp that provided the sock performs well as a sock, having some other potential feature that may assist in performance and recovery is a positive thing and worthy of trying out. You can make your own determination.

SAlomon S Lab NSO sock line details

As noted above Salomon is offering the NSO sock line in three variants, each focused on different run “lengths”- short run, mid run, and long run. The primary differences are in the level of cushioning and compression offered by each variant with the highest amount of cushioning and compression being in the long run sock. All of these socks are designed enanitiomorpically, i.e. the socks pairs have a left and right.  But there are other differences as well and I will review them here.

Nso short run

The Short Run variant of the NSO sock is a minimalist sock that provides a thin layer of cushioning at the heel and toe and thin or super thin materials everywhere else. For those that like a minimalist sock (as I do), this version of NSO line will likely be appealing.

Top side of the NSO Short Run sock. Note the super thin material through the mid-section and the four “stripes” across (and around) the sock in the forefoot. The “stripes” have a slightly sticky silicone material coating that is intended to help hold one’s foot in place under demanding situations like steep downhills, steep ascents, and technical trail.

This model has the least amount of technologies in the NSO line but does include the oxide particle fiber material (Quantum Energy). The other features of this sock are extreme thin-ness in the mid-foot and ankle area and represents one of the most minimal of socks out there for trail running.

Salomon NSO Short Run. The entire NSO line in enanitiomorpic- meaning all socks have a left and right.

Minimalist socks are my preference and the NSO Short Run is an outstanding minimalist offering. They are very lightweight and have a skin-fit with flat seams. The heel and forefoot cushioning is noticeable but not annoying. The silicone “stripes” intended to keep the foot from moving within the shoe seems a bit unnecessary. It is my position that the fit of the shoe is what will take care of that — buy a properly fitted shoe and there will be very little movement within the shoe. Another reviewer of the Salomon NSO sock line** thought highly of the silicone “stripes” as they could make a badly fitting shoe work better. Well, why run in a badly fitting shoe? Particularly if you are using Salomon shoes with EndoFit, SensiFit and the other “fit” technologies that make Salomon the superior shoe for fit. Let the shoe do what it is supposed to do and do not depend on a sock to fix a badly fitting shoe. The “grip stripes” are present in all three variants of the NSO sock line and the comments above apply to all the variants.

Salomon NSO Short Run. A very minimalist sock with a skin fit and lots of technology.

The “short run” sock has performed very well in a wide range of conditions from early spring wet and snow to super dry and “moondust” summer conditions. They dry quickly, are transparently comfortable, breathe exceedingly well, and do a good job of keeping tiny dust particles in dry conditions away from the foot. The sock is very thin in certain areas (e.g. across the middle of the foot where shoes are generally cinched down). This eliminates any concern with thick, bunched up, fabric in this critical area. As a result the socks essentially disappear and just do the job of protecting your feet from abrasion and dust. Is the NSO technology doing anything? I don’t know. I do know that these socks are a great choice for those who like a minimal sock. This is my current go-to sock and , as indicated above I bought six pair of this “short run” variant for daily use.

NSO Mid Run

The Mid Run variant in the NSO line adds a bit more cushioning throughout the sole and mid-foot of the sock whilst maintaining all of the technologies in the “short run” model. This variant also includes something called Nano-Glide, a polyamide coating on the fibers that minimizes friction between skin and the sock. The Nano-Glide technology has been used in Salomon socks for at least 7 years and I can attest to it’s efficacy. I have never had a blister, hot spot, or even a red spot while using socks with the Nano-Glide fiber coating. My only gripe- Nano-Glide socks can be difficult to slide through certain tights. It is apparent that the materials that some Salomon tights are composed of “catch” the Nano-Glide coating and make it difficult to get your foot through when putting on the tights. I’ve noticed that the latest Salomon tights that I have do not exhibit this issue.

Top side of the NSO Mid Run sock. Note the compression knit through the mid-section and the five “stripes” across (and around) the sock in the forefoot. The “stripes” have a slightly sticky silicone material coating that is intended to help hold one’s foot in place under demanding situations like steep downhills, steep ascents, and technical trail.

There is also a limited amount of compression in the mid-forefoot area and around the lower part of the ankle. Based on available evidence in many studies, compression shows no reliable efficacy but there may be a significant placebo effect. So although there may be no real performance advantage, you might “feel” better with compression and, to be honest, that is what matters particularly in long runs and races. I do not have this placebo effect so compression is not something that I look for, in fact I find it to be annoying in some cases. But — to each their own!

The Salomon NSO Mid Run adds some compression knit in the mid foot, forefoot, and lower ankle, as well as NanoGlide- an anti-friction polyamide coating on the fibers.

This is still a very lightweight sock and can be viewed as the Short Run with the anti-friction NanoGlide technology and a small bit of compression mixed in. I find the fit to be excellent and the cushioning unobtrusive. They dry very quickly and provide high performance  for the basic purpose of a sock- protecting your feet from abrasion and dust. The Short Run variant is my daily-use sock but the Mid Run is often in the mix and it is hard to tell the difference between the two when running. So if you like a bit more cushion the Mid Run might be an option.

Salomon NSO Mid Run. The compression knit is more visible from a side view.

NSO Long Run

The Long Run variant is the sock that Salomon designed specifically for Francois D’Haene, the long distance specialist on the Salomon team. I’ve seen pictures of the Salomon designers/engineers working with D’Haene on these sock and concentrating on features in and around the ankle. As anyone who has run a 100 km+ race will know, ankle protection and comfort is critical to an enjoyable day and it apparent that Francois is particularly interested in this.

Top side of the NSO Long Run sock. Note the substantial compression knit material through the mid-section and ankle. The four “stripes” across (and around) the sock in the forefoot have a slightly sticky silicone material coating that is intended to help hold one’s foot in place under demanding situations like steep downhills, steep ascents, and technical trail. This variant also includes a padded area at the medial malleolus and a directional knit pattern at the lateral ankle. Note: left and right are reversed in this photo, so the medial malleolus padding is on the medial side of the socks — not on the lateral side as shown here.

The Long Run variant is basically a Mid Run with a lot more compression throughout the mid foot and ankle area. The sole, heel, and toe of the sock is virtually indistinguishable from the Mid Run including the NanoGlide polyamide coating technology. The Long Run has a couple of other features: a padded area at the medial malleolus (the knobby ankle bone) and a directional knit structure in the lateral ankle area. I understand the padding since, as when one gets tired, it is common for the medial malleolus to get “scuffed” by the opposing foot as it comes by on the run stride. You’ll see this after a run or race where scuff marks are evident in this area. In long runs and races this can lead to abrasion and pain so putting a bit a padding there makes sense. The directional knitting on the other hand seems superfluous. It falls in the same category as KT tape- useless. There is no reliable evidence that such minuscule directional tension does anything efficacious. But again, there may be a significant placebo effect so some may “feel” a difference.

The Salomon NSO Long Run showing the substantial compression knit throughout the forefoot, mid foot, and ankle. Also note the padding at the medial malleolus.

Side view of Salomon NSO Long Run sock showing compression knit and padding at ankle. Note that the entire sole of the sock is virtually identical to the Mid Run variant.

The Salomon NSO Long Run variant also includes a directional knit pattern oat the lateral ankle. Does this do anything? Probably not, but it looks cool!

The Long Run variant is a bit more of a chore to get on due the compression knit but once on it is very comfortable. Even with all of the added features it is still on the minimalist side of trail socks currently available. I find the fit to be excellent and the comfort is great. It is maybe a bit too much sock for me but I did run in this sock for a 30 km mountain race with about 1500 m (5000 ft) of climb and descent. The sock performed well and essentially disappeared- meaning that I had no thoughts about socks during the race which is exactly what one wants. I thought that a bit of extra cushioning might be desirable for a race that started out with a 6 km (4 mi) 750 m (2500 ft) climb followed by a 5 km (3 mi) 500 m (1500 ft) descent. Perhaps there was an advantage but the difference I felt was minor if at all.


As with all Salomon S Lab products, these sock are expensive at $28-$30 a pair, depending on the variant. But they do provide a lot of technology and some unique features all while maintaining a lightweight, minimalist ethos. Also, if the socks are as durable as other Salomon socks have been in the past, you will be using these for years and the price point then looks a bit better.

bottom line

A high technology line of high performance socks that will appeal to many trail runners, independent of specialization — from technical trail aficionados to long distance grinders. Does NSO do anything? Who knows but as with any new technology time will tell. In the meantime, the Salomon NSO line of socks offer a minimalist solution for whatever “style” of trail running you might partake in- all with excellent fit, protection, and support. And they all dry very quickly. For me it all comes down to whether or not a sock “disappears” when I use it. These do and I expect to be training and racing in these socks for years to come.

final note

As indicated at the outset, thee NSO line includes a “Leg Up” variant that is a full knee height compression sock. Although I have tried this sock out, I personally find the compression to serve no purpose other than to be annoying. So I provide no full review here. There are many others that find compression to be functional and I encourage those that do to check out the “Leg Up” NSO variant. If there is any model in this line where the NSO technology is likely to be apparent it will be in the “Leg Up” where the NSO fiber material is covering toe to knee and any FIR effect that is extant should be maximized.

*Note: Salomon also have an S Lab NSO Tee and an S Lab NSO Half Tight that utilize the same technology.

**Note: a couple of the pictures of the socks in that review are incorrectly correlated with the sock type- specifically they show the NSO Short Run as the Speed Support and the Speed Support as the NSO Short Run.



Salomon RX MOC 4.0 “Recovery” shoe – Review

I have reviewed all of the previous generations (Gen 1, Gen 2, Gen 3) of the Salomon Relax “recovery” shoe and have found the products to be very comfortable and to provide support that helps with foot recovery after long and/or technical trail runs/races. The RX Moc has been a daily wear shoe for me ever since it was offered in 2010/11 and the 4th generation is no exception.

Salomon “Relax” RX MOC 4.0

RX MOC 4.0

The outsole of the RX 4.0 is the same as in the 3.0 version and provides plenty of grip for general casual use and even the occasional foray onto trails and rock when camping/traveling.

The RX Moc 4.0 is an evolutionary product that builds upon the features, design, and function provided by the prior generations of the product. These functions include high breathability, a very “cushy” midsole, a grippy outsole, and, most importantly, a footbed design that provides support around the edge of the foot. All of this carried forward in the 4.0 version along with adding a couple of new features/materials.

But the most important feature is the “cupped” footbed that supports the edges of ones feet and that allows for comfortable walking/hiking even after a long trail run/race. As I wrote in the earlier reviews:

“The concept is that after running there are certain muscles in the feet that are more impacted by long training runs/races and require additional support after the training run or race for efficient recovery.”

My experience is that the concept works- but even if it is a placebo, the shoes are super comfortable, machine washable, and highly durable.

Top view of the RX 4.0 showing the redesigned mesh upper but the same toe bumper of the 3.0 generation.

Side view of the RX 4.0 showing the sculpted last carried forward from the 3.0 generation.

changes from 3.0 to 4.0

The primary change with the 4.0 vs the 3.0 is that the heel counter is now designed to be crushed down and thereby allow for use of the shoe in either a traditional way (with heel counter) or as a slip-on (e.g. like a clog). Many users of past models of the RX Moc have chosen to just ignore the heel counter and use the shoe as a slip on. Unfortunately the heel counter was not designed to be crushed or to be rubbed by the heel. As a result those that used the shoe in this way (including myself) found  that the crushed heel counter developed holes and this compromised use as a traditional shoe. The new design allows for both comfort and durability in switching back and forth between use types- it’s a great idea! All one has to do is remove the insole, push the heel counter down, and replace the insole- presto, you now have a slip-on.

After listening to their users, Salomon have provided a heel counter that is designed to be folded down to allow the RX 4.0 to be used both as a traditional shoe and as a slide-on. Many users of past versions did this anyway but the heel counter would wear out (develop holes) and limit the use of the shoe. Now this feature is designed in- great!

Just remove the insole, push down the heel counter, and replace the insole and presto- you now have a slip-on!

The other significant change from the 3.0 version is the insole. The 3.0 had a two layer insole that was comprised of a cushy polymer underlayer with a thin, grained faux-leather top layer. The 4.0 version has a single cushy polymer insole without a faux-leather layer. My use found that eventually the faux-leather insole layer began to delaminate from the underlayer. This occurred after many (about 25-30) machine washings. Such washings are rather rough on any adhesive system so this experience is expected. However, the faux-leather never fully delaminated and the small amount of delimitation never affected the performance of the shoe. In any case, Salomon have decided to replace the faux-leather with a one-layer system which, so far, is just as comfortable and will likely be as durable.

A minor change with the 4.0 is the mesh fabric pattern on the upper. The 4.0 has a two-piece pattern that wraps diagonally across the top of the foot whereas the 3.0 pattern is a two-piece “serpentine” pattern that is longitudinal. I do not feel a substantial difference between the two with the exception of the 4.0 feeling a bit more “huggy”. This could just be due to the fact that the 4.0 is new but time will tell.

One of the nicest aspects of this shoe is the washability. One can just throw these in the washer and let them air dry and a shoe that was quite dirty comes out looking as new. This was particularly important for the “orangey” S Lab 3.0 model that I have been using since 2013 as it would get quite dirty given daily use across many activities, including camping. I expect the same to be the case for these black 4.0’s


As mentioned above, the outsole is nicely grippy for a casual, street shoe. The outsole, however, has areas that are not particularly durable. The area within the rubber tread layer that nearly circumscribes the sole is the “chevron” pattern area that appears to be made of “midsole-type” material (likely EVA). This material does not wear well and I have found it to be essentially smoothed out within about three seasons of my daily use (April-November). That’s still a lot of use and the rubber area is still intact and quite grippy, it’s just that the total grip of the outsole is somewhat diminished. This has not prevented me from using the shoe as it still performs well even without the “chevron” pattern being present- now six years later! Just something to note.


As this is a casual shoe, the colorway choice can be important for some users. The 4.0 is available in black with a black midsole (as shown here), blue with a white midsole, and red with a white midsole. That is quite a limited choice. In the US only the black and blue variants are available. I find the white midsole to look a bit “clunky” but that is just my opinion.

In the past there has been an S Lab version of the RX Moc and these variants were what I have reviewed earlier. The S Lab variant was just cosmetic- special colors and S Lab badging, so the shoe itself was the same. The 4.0 does not offer a S Lab variant for the 2019/20 season. Perhaps there will be one in the future. I must say that I like the black version as it blends well with many situations- athletic, casual, and, for some here in the mountains, even for more formal occasions. I likely will not wear any other casual shoe throughout the spring-summer-fall.


$75 US. As usual a bit on the high side but given the comfort, the foot recovery aspects, the flexibility to transform the shoe from a traditional fit to a slip-on, and the durability that I have experienced, this shoe represents a reasonable value.

bottom line

A nice evolution of a proven casual/recovery shoe with high comfort, durability, and flexibility. Highly recommended!


Salomon S/Race Skin skis – Pink Pomoca Paradise


One of the most formidable barriers to classic skiing for newbies and experienced skiers alike is the challenge one often faces to pick and properly apply an effective kick wax for the prevailing conditions. Now, this selection  is rather straightforward in what are known as “hard wax conditions” where the simple application of a natural or synthetic wax composition for the prevailing temperature range performs very well. In such dry, compacted powder, non-aggresive snow crystal conditions, no binder is needed and fussing with mixes of wax is of little value. Just apply the wax and go. However (except in the Rocky Mountain West and a few other places) such conditions rarely occur. Typically, a near-infinite number of unpredictable (and often changing) conditions are instead what the skier has to accommodate. To be successful in reliably waxing for such conditions requires years of experience and an increasingly vast encyclopedic knowledge of “what works when” and continued attempts at new solutions with a similarly increasingly vast array of wax compositions. It is a situation that deters many from classic skiing and is the reason we see such a predominant number of skiers in the sport who choose to only skate.

Unfortuantely, the “glacial-like” innovation and technology development rate that is extant in the cross country skiing world has led to very few kick/grip solutions for skiers. Way back in the 1970’s “fish scale” skis (or “Crown” skis) were developed that at least provided reliable kick in a wide variety of challenging conditions. However, ski glide with fishscale skis is highly compromised and as a result makes skiing with such skis not very much fun on the downhills- not to mention the handicap in improving and optimizing one’s classic technique with the deficient glide.

More recently, technology has been developed to facilitate good to very good kick and good to very good glide for conditions right around freezing (32 F, 0 C) and particularly when snow has recently fallen. This technology is called “Zeros” and utilizes a rubberized kick zone composition that can be “roughed-up” to allow for effective kick in conditions that typically prevail right around freezing. These skis were used extensively at the 2010 Olympics in Whistler BC Canada (also know as the “Rain Olympics” because of all of the rain and super wet snow that fell during the competitions). “Zeros” have since become an essential part of any competitive ski er’s quiver since there is still very little in the way of waxing technology that can effectively deal with such conditions. Both competitive skiers and recreational skiers are utilizing zeros at an increasing rate given the warming that is clearly evident throughout the world, i.e “zeros” conditions are becoming more and more common.  Even here in the relatively dry and cold Northern Rockies, we use our zeros about 20% of the time (or about 30 sessions in a 150 session season). Such skis are indispensable since there really is nothing that works as well in “zeros” conditions.

Even more recently, ski manufacturers have slowly developed a kick technology for Nordic skis that utilizes a “skin” material that has been in use in Back Country and Ski Mountaineering for decades. Such “skins” simulate what actual animal fur “skins” did for ancient skiers in preceding millennia and that currently do for BackCountry and Ski Mountaineering skiers today. Originally skins were made from seal skin (hence the term “skins”) but all current ski skins are man-made woven cloth (mohair) or synthetic derivatives (e.g nylon fibers) with better durability, climbing performance, and glide speed. These man-made and Synthetic “skins” have been developed over many decades and have been broadly adopted by cross country ski manufacturers in about the last 5 years.

Salomon S/Race Skin ski- a great option for training for competitive skiers and for general use by recreationalists.

All of the major cross country skiing manufacturers now offer skin skis. Fischer, Madsus, Salomon, Atomic, and Rossignol all are also now offering numerous models including those specifically for racing. Each has their own approach to accomplish good kick and glide in difficult conditions with different skin compositions and designs. In this post I review the Salomon S/Race Skin ski as it compares to waxed skis and other synthetic kick solutions i.e. “zeros”. I will not compare Salomon S/Race Skin skis to other manufacturers models as I do not have access to skin skis that have been hand-picked for my biometrics and skiing style. Since ski flex is so important in ski performance it is of little value to compare skis without matching such parameters. So what will be described here is first-hand experience with comparisons of hand-picked Salomon S/Race Skin skis to other hand-picked Salomon racing classic skis in various snow conditions. Similar observations are highly likely to obtain with other manufacturers products in similar conditions and comparisons.

salomon s/race skin ski

The Salomon S/Race Skin ski is a combination of the latest race ski structure and flex characteristics with a race base, universal grind, and a state-of-the-art racing skin overlay. By overlay it is meant that the skin material is glued to the base and is not inlayed into the ski base.

Salomon has been working with the Switzerland-based pre-eminent synthetic skin technology developer and synthetic skin manufacturer Pomoca to further develop and apply Pomoca technology for use in both racing and recreational cross country skis. Since it’s beginnings in the 1930’s Pomoca (incorporated under this name in 1957) has been challenging the performance boundaries of “climbing skins” for touring and back country skis. Initially utilizing mohair fabrics, Pomoca revolutionized the “skins” market with the introduction of synthetic, nylon fiber-based skins in 1975. Since then they have been evolving the technology to improve both climbing and glide characteristics.

For racers, the Pomoca Race Pro 2.0 Vertical skin composition has been a reliable and fast choice for Ski Mountaineer racers in primarily vertical races. With acceptable glide combined with sufficient grip for steep ascents, the Pro 2.0 Vertical product is a mainstay at all Ski Mo competitions where races involve only (or primarily) vertical ascending. Realizing that such skin compositions could be effectively used for cross country skiing, Salomon and Pomoca have collaborated to bring the S/Race Skin ski to the market.

Pomoca Race Pro 2.0 Vertical Ski Mountaineering racing skin. Pomona claims that this skin is a proprietary composition some details of which may also be used in the Salomon S/Race Skin cross country ski.

As already mentioned, the S/Race Skin ski from Salomon has a skin material that is very similar to (or exactly the same as) Pomoca’s ski mountaineering Race Pro 2.0 Vertical skin. This 100% mohair skin composition** is glued to the kick zone of the specially constructed ski. The skin material is pre-treated by Pomoca to ensure what they call “anti-glopping”. This is basically a hydrophobic coating that reduces or eliminates icing and should last the life of the skin according to the manufacturer. The S/Race ski itself is claimed to be the lightest classic ski that Salomon have ever manufactured and includes a unique construction specifically designed to maximize kick and glide with skin material.

Salomon S/Race Skin ski showing the Pomoca skin appliqué that is very similar to (or exactly the same as) Pomoca’s Ski Mo Race Pro 2.0 Vertical skin.

The Salomon technical product literature provides the following information on the specific design and material aspects of the S/Race Skin ski:

Here is a higher resolution image of the Pomona fabric structure showing the high density of multiple-fiber “beams” that allow for grip and lay down when gliding. The high density of “beams” is said to be a key element for attaining exceptional glide.

Detail of the Pomoca skin material utilized by Salomon in the S/Race Skin ski showing a high density array of directional, multiple-fiber “beams” and the underlying cloth structure through which the 100% mohair fibers are woven. There is conflicting information about the composition of the S/Race Skin skin material. Some in the US indicate that the skin is synthetic, others say it is composite of mohair and synthetic, and the information provided by Salomon above says the skin is 100% mohair.  Who knows? In any case it has very good glide compared with other competing skin materials.

The Salomon S/Race Skin ski brings together a number of technologies into a single product specifically designed for high-level training and, potentially, racing. I think Salomon have done exceedingly well in this venture as my on-snow use described below will support.

on-snow performance

We received a pair of S/Race Skin skis just before leaving for a training camp in West Yellowstone the week prior to Thanksgiving. These skis had been picked for us by the Ski Whisperer at the factory this summer. Our expectations were that these skis would be used on difficult waxing days when we wanted to classic ski and did not want to fuss with wax. The skis would also be used for teaching at the local resort. We only ordered one pair because other users of skin skis (from other manufacturers) noted that, in general, cross country skin skis had great grip but they were very slow on the glide side. We wanted to see how the Salomon product performed prior to making an investment in two pairs.

West Yellowstone had a decent snow pack when we arrived but the next day it rained all day leading to saturated snow conditions where zeros were working well. That night the temperature fell significantly, the snow dried out, and the excellent grooming crew in West Yellowstone did a great job of setting the tracks. We went out with the S/Race Skin skis and a pair of racing skis with a “covered klister” system that was (we were told) being utilized by all of the elite-level skiers who were training that day. Arriving at the trail system we found the tracks and decks to be nicely packed but with a substantial amount of ice and the tracks were clearly glazed. The temperature was about -10C (15F). Out we went on Rendezvous, Jerry’s Journey and then the Dead Dog loop. Both ski pairs were performing well for grip, although the skins were “bomber” and the covered blister was very good but not “bomber”. As far as glide, we were astonished when the skin ski was out-gliding the waxed racing ski in the track! This continued throughout the session where the skin ski was either out-gliding the race ski or they were even. Amazing! On the deck however the skin ski would catch whatever loose snow there was and slow down a bit- and also “sing” (make a high pitched sound) which is never a good sign for glide optimization.

A speed test on a steep downhill in the track showed that the S/Race Skin skis will support speeds in excess of 48 kph- about as fast as we currently go on our waxed racing classic skis. On the deck this reduced to about 35 kph on the same hill. But remember- skin skis are “grab and go”… no muss, no fuss and therefore yielding just that much more time on trails and no frustration with figuring out the “right” wax combination. We call the S/Race Skin ski “Pink Pomoca Paradise”!

We continued to use and compare the S/Race skin ski to other waxable classic skis that we brought with us throughout the changing conditions we encountered. We had some new snow that was set without glazed tracks and the skin ski was clearly slower but not by much. As noted above, the skins will catch and slow down on loose unpacked or loosely packed powder that is often found on the decks so staying in the track will maximize glide. However, even in the track in slightly loose snow conditions the skis will slow down relative to a waxed equivalent. The skins also do not exhibit “free” glide in striding and one can feel the resistance in the glide phase on each stride. It is a small resistance that is real and would add up over the course of a race. But this is a small price to pay for the “grab and go” convenience and the consistently “bomber” kick, particularly for training.

The S/Race Skin skis were in such demand that it was coin toss as to who got them on any given day, so we called the Ski Whisperer and secured another pair, which has since arrived and has been found to provide performance that is equivalent to the first pair.

how to use s/race skin skis

Although the Salomon S/Race Skin skis can be fast in certain track conditions, they will likely never be a “race” ski on race day. This is because any well-informed and experienced classic ski waxer should be able to put together a wax program that works for kick and has superior glide  for the conditions. However, for training the S/Race skis shine as they will enable a classic training session in virtually all difficult conditions where getting the wax right would be a significant effort. For me, training sessions are all about heart rates and the S/Race Skin will allow for a straightforward “grab-and-go” solution that ensures I can get the work done without any hassle. It may not be the fastest session but at least I can get the session completed and not spend time on the trails frustrated trying to get good kick. Rather I am just bombing up the hill repeats and challenging the limits of what the session is designed to work on.

Another primary use for the S/Race Skins is as a technique development tool. Here the “bomber” kick will allow one to concentrate on getting the split second timing right and therefore bring together all of the dynamic movements required to refine and optimize a good classic stride. Many skiers suffer from this on-snow development and refinement because they are on skis that are not kicking well. As a result the all-critical timing and dynamic movement coordination never come together for long enough to allow for the focused work, repetition, and myelination to take hold.

Finally, the S/Race Skin skis are ideally suited to those just starting out with classic technique- for all of reasons given above for classic ski racers: reliable “bomber” kick, “grab-and-go” convenience, and reasonable glide (and great glide in icy conditions). New classic skiers  consistently bring up all of these factors when discussing their foray into the classic technique. Hopefully the new generation of skin skis will encourage more and more skiers to give classic skiing a try and lead to a larger classic ski population out on the trails.

bottom line

“Grab-and-Go” convenience, “bomber” kick, and good to great glide in a lightweight, well designed ski for training for competitive skiers or as a daily ski for recreationalists. Highly recommended.

Update 31 Dec 2017: We have skied on the skin skis for a number of additional sessions and in additional conditions. A few days ago the snow conditions consisted of newly fallen warmish powder snow (20-23F) that had been groomed early in the morning. The air temperature warmed to about 29-31F and the tracks glazed over but did not ice. Bumble was on the skins and Bee was on Carbon skate skis with the same wax and similar grind. In the track the skins out-glided the skate skis- by a significant margin. On the deck the skins would catch any loose snow and slow down compared to the skate skis but they were still gliding well. So the lesson here is that there will be conditions where the skins may be in the running on race day and it would do one well to consider taking the skins along to any race where the waxing might be tricky. I know that we will be taking them.

* or “mohair” as some prefer, although mohair (a woven cloth made from Angora goat hair) is only one of a number of “skin” types e.g. some skins are made from synthetic fibers (e.g. nylon) or mix of synthetic and mohair fibers

**There is conflicting information about the composition of the S/Race Skin skin material. Some in the US indicate that the skin is synthetic, others say it is composite of mohair and synthetic, and the information provided by Salomon above says the skin is 100% mohair.  Who knows? In any case it has very good glide compared with other competing skin materials.

Salomon Sense Ride – not impressed

The Salomon Sense Ride trail running shoe was pre-announced at the Summer 2016 OR  and became available in June 2017. I received a pair a couple of weeks ago and have put about 150 km on them in a 50/50 mix of smooth buffed singletrack and rocky technical trail. After reading a review by some trusted users I was looking forward to a potential lower cost shoe that had much of what the S Lab Sense Ultra 2017 offers and could be used for the bulk of training, saving the S Lab Ultra for races and more technical efforts. Well, miracles are fantasy and that is what has prevailed in this case. Based on my running mechanics, style, and terrain the Sense Ride is no S Lab Sense Ultra.

Salomon Sense Ride is a cushioned trail running shoe with some new anti-vibration technology (Opal inserts across the footbed). The colorway shown here is a dark blue with orange accents- the orange is much deeper in hue but the sunlight in Sun Valley is currently being filtered through a bit of smoke from fires from the north and south and this affects the color sensitivity calibration of my camera image sensor for directly reflected light. A truer color representation is evident in the indirectly reflected light pictures below.


The Sense Ride has the typical “rocker” profile that is common among shoes with higher cushioning.

A mild but effective rocker is used on the Sense Ride.

All of the Salomon fit technologies are present including Endofit (a separate inner sock-like element engaging the foot), Sensifit (outer polymer overlays integrated with the QuickLace system), and the QuickLace system. The tongue is minimally cushioned.

Flexibility is good whilst still including the ProFeel film technology for rock protection. The flexibility is accomplished with three lateral flex axes that traverse the width of the outsole. There is a similar flex axis at a slight diagonal across the lateral heel area. Proprioception is OK but is inferior when compared to the Sense Pro Max high cushion shoe, and is nothing like that found with the S Lab Sense Ultra.

The stack comes in at 27mm heel/ 19mm forefoot which is a nice “cush” level and 1mm more than that offered in the S Lab Sense Ultra. But this shoe also has Salomon’s new vibration-reduction technology called Vibe which, in this shoe, includes a full-foot insert of the vibration-absorbing Opal material. This is different than in the Sense Pro Max (and the S Lab Sonic 2) where the Opal is two separate inserts- one in the forefoot and one in the heel. The Vibe technology is nicely described in this review of the S Lab Sonic 2. I am not a fan of the Vibe technology and there will be more on that below.

The outsole utilizes the Premium Wet Traction ContraGrip material which is an excellent performer across the board for the highly variable conditions of trail and mountain running.

My size US 7.5 (40 2/3 EUR) weigh in at 233 gms (8.2 oz) which is well within the weight range for a racing shoe. This shoe is not a Salomon racing product as it is intended for general training and trail running, but it could clearly be used as a racer.


The Sense Ride upper is constructed in a fashion that is very similar to the S Lab shoes and includes all of the fit technologies that have made the S Lab shoes such a near-optimal fit benchmark in trail running products. As mentioned above, these fit technologies include EndoFit, SensiFit, Salomon QuickLace, and a shaped foot bed. The Sense Ride also has a substantial OrthoLite foot liner which provides a bit more cushion.

The upper mesh is a reasonably light weight material but clearly heavier and less flexible than the mesh used in the S Lab Sense Ultra. This mesh does not drain as well or dry as quickly as the S Lab Sense Ultra- both of which are important considerations for broad use on trails.

The Salomon Sense Ride has a very large volume that does not accommodate smaller feet. The shoe is built on a very different last to that used for the S Lab Sense Ultra. It seems to be designed for bigger, beefy feet. Drainage and associated drying are OK, not great

I am not sure how this happened but somehow Salomon have managed to totally screw-up the fit of this shoe even with the superior fit technologies being employed. First off, the upper has too much volume and it seems that Salomon is trying to accommodate some foot shapes that are so voluminous that the standard fit technologies are not capable of providing a secure fit for lower volume feet. Second, there is a large difference in the shape of the last for the Sense Ride. This is exhibited when one puts the Sense Ride shoe on where it just easily slides on as if you were putting on a loafer- with support and fit on par with such a shoe (or a Hoka or Altra). The S Lab Sense Ultra is built on a very different last that leads to a fit more like a cross country ski boot where the foot slides in with a bit of constraint and then engages in a final position that is snug and fully supporting around the entire foot leading to a high level of control and proprioception. Control and proprioception are not strong points for the Sense Ride.

I thought that perhaps I needed to size down and I tried this with a US 7 (40 EU) and found no improvement in fit and the shoe at this size was close to being too short for long run comfort. So sizing down will not fix the problem.


With a 27mm/19mm stack this shoe should feel ultra-cush but such does not obtain. I find the “ride” of the Sense Ride to be firm when compared to the S Lab Sense Ultra and this is obviously due to the inclusion of the vibration-reducing Opal inserts. Just as I found with the Sense Pro Max, the Opal material leads to a somewhat jarring experience on trails and this is something that, for me, is undesirable. I still do not have, nor have Salomon offered, an explanation of why the mid-to-high frequency vibrations that the Opal supposedly eliminates are so important. I expect that there could be some correlation to muscle micro-tearing but that is going to be very much a function of individual biomechanics and biometrics that a lot of data would need to be collected to support any claim for broad efficacy. As a lighter weight runner I find the material to not be an improvement. A heavier runner might have a different experience.


The outsole has a design that is essentially identical with the S Lab Sense Ultra and uses the same Premium Wet Traction ContraGrip material. The lug design and material combine to provide some of the best broad-use traction performance available today. As mentioned earlier three shoe width wide flex axes are included in the forefoot with a smaller axis at a diagonal at the heel. These add flexibility to a shoe that would otherwise be very stiff, given the full foot Opal insert.

Salomon Sense Ride outsole. Nearly identical to the S Lab Sense Ultra in design and materials. One of the best performing outsoles currently on the market.

This outsole is very durable as i now have over 1500 km (1000 miles) on a pair of S Lab Sense Ultras with hardly any sign of wear- even in the rough, rocky training terrain that I use on a daily basis.

running performance

Primarily due to the very poor fit but also due to an overly firm ride, the Sense Ride exhibit a weird combination of lack of control with a somewhat jarring feel. The worst of two worlds. On any trail even hinting at “technical” these shoes start to detach from my feet and lead to a disjointed and disturbing trail experience. Although the Opal inserts begin to “break-in” after about 30 miles, the firm ride never seems to dissipate.  Compared to the super-high control, very high proprioception, and super-cush ride of the S Lab Sense Ultra the Sense Ride are embarrassingly bad. After 150 km of hoping for “break-in”, these shoes have been put to the back of the shoe closet where they are likely to gather a thick layer of dust.


$120US. A seemingly great price considering it is a Salomon shoe with all of the superior fit technologies and a new vibration reduction material. But given just the poor fit the shoe has zero value.

bottom line

A poorly fitting, low proprioception, firm riding shoe that cannot be recommended*.

*note: I am a lighter runner (125-130 lbs) with a predominant forefoot strike and a high cadence (190-200 spm @ training pace). A heavier runner with a midfoot-to-heel strike and/or a lower cadence may find a very different feel in this shoe.


Salomon S Lab Sense Ultra 2017 – 1200 km Update

This is a short, and final, update on the performance of the 2017 Salomon Sense Ultra. As indicated in an initial review and a 300 km update, The Sense Ultra has performed exceedingly well… and this has continued  in many additional kms. I can say without hesitation that if you are looking for a shoe with outstanding technical capabilities along with “long run” comfort, the Sense Ultra should be at the top of your list.

Salomon S Lab Sense Ultra 2017 after about 1200 km of use on a 50/50 mix of rocky technical and buffed out single track in the Norther Rockies of Idaho’s central mountains. Even after this much use the shoes are entirely intact with plenty of remaining cushion.

In about 1200 kms of use on a 50/50 mix of rocky technical and buffed out single track in the Norther Rockies of Idaho’s central mountains, the Sense Ultra have held up very well and are still going strong with performance that has hardly diminished. From the excellent proprioception and outstanding fit to the optimized level of cushioning, I have experienced no significant changes. The outsole, as usual, shows very minimal wear even on the abrasive, rocky terrain that I typically run on here in the Northern Rockies.

Outsole of the 2017 S Lab sense Ultra after about 1200 kms of use. Hardly any noticeable wear except in the expected area of the lateral heel typical of wear with my running gait. Dry and wet traction is still at the highest levels and grip on rock continues to be excellent.

The shoe construction, materials, and fit are intact and continuing to perform at the highest levels. The Sense Ultra are the most durable shoes I have experienced in many years of about 3500 kms per year on rocky mountainous terrain. Very impressive.

I cracked out a new pair of Sense Ultras for a 25 km mountain trail race with 1000 m of climb and descent a couple of weeks ago and barely noticed the difference between the well used first pair and the new, out-of-the-box pair. Quite remarkable!

They were not as “rocker” to start with but the Sense Ultra exhibit a significant “rocker” after 1200 kms of use.

One concern I noted at the outset was a “wrinkle” that had formed on the forefoot upper mesh that looked like it might develop into an area that would see excessive wear and potentially develop a hole. That did not happen as the upper mesh material is durable enough to withstand the extra abrasion and strain of the “wrinkle”.

Area on the medial forefoot that developed a “wrinkle” early on. Associated concerns over premature wear-out have not materialized and the upper mesh fabric shows no evidence. of breakdown

If there is one issue that is worthy of note, it is the fit as it concerns steep (30%+ grade) and/or typical mountain grade (5-20% grade) fast (sub 6 minute pace) downhill running. I hesitate to bring this up as I question my abilities in downhill running, but I find that the larger toebox design of the Sense Ultra leads to excessive movement of the forefoot upon plant and concomitant loss of proprioception and increased frictional forces on the bottom and sides of the cutaneous forefoot. This is something that I have gotten used to but I think that the shoe would be improved if the forefoot fit was bit tighter. As the fit in the forefoot is quite a personal thing dependent on exact foot shape and other factors, my experience may not be generally applicable. I guess this is the type of thing that Salomon hopes to provide solutions to with the S Lab ME:sh program.

bottom line

I say with confidence that the Salomon S Lab Sense Ultra 2017 is a “sweet spot” technical mountain trail running shoe suitable for both training and racing with excellent durability that retains significant fractions of cushion throughout the life of the shoe. The shoe is well worth the price of $180 US on a cost per mile basis. I expect to get even more kms out of this shoe as it is still very comfortable at 1200 kms. Highly recommended!

Salomon S Lab Sense Ultra 2017 – 300 km Update

Note 20 June 2017: Salomon have just announced the S Lab Sense Ultra 2 which is said to be available Spring 2018 (likely in Jan/Feb 2018). The new version includes more cushioning and a wider last in the midfoot. Salomon have also incorporated some technology from their cross country ski boot designs for skate boots- a stiff plastic element that crosses over the foot just below the ankle and is integrated with the speed lacing. This element is called “Skin Guard” and supposedly allows for better control on descents. Although not as adjustable as the ski boot equivalent, the “Skin Guard” looks like it might be an interesting development. Unfortunately, the shoe is now heavier at 300 gms for size 9 (US). Pictures and brief description here.

I have provided a 1200 km update on this shoe.



Even though we have only just finished up the ski season (the last grooming was this past Sunday (7 May), I have been able to get out running a fair bit. The epic snow year means the trails are opening up slowly so I have not spent much time up high on the more technical rocky terrain as these areas are still under 3-6 feet (1-2 m) of snow. But I have been able to find some dirt, some rock, and, mixed with some snow fields, pieced together some reasonable length runs of 15-25 km. In total I have about 300 km on the 2017 Sense Ultra at this point with about a 50/50 mix of dirt/rock and snow.

After about 200 kms, there hardly any noticeable wear on the outsole, no excessive wear on the uppers (even though I have postholed through a fair share of crusted snow fields where abrasion is very high), and no noticeable reduction in cushioning.

The performance of these shoes has been outstanding! Salomon have truly hit a “sweet spot” of cushioning, grip, trail feel, and weight. The grip has been superior in all of the conditions that I have been able to test- dry and wet dirt , mud, clay mud, snow, ice, and wet and dry rock. All of these on rolling and steep (up to about 40% grade) trails. The trail feel is very good but not as transparent as in the S Lab X-Series (Sonic) and S Lab Sense. The weight (about 260 gms for these 7.5 US 40 2/3 EU) is not as noticeable as I thought it might be. But the most prominent feature of these shoes is the mid-foot support and the added cushioning.

The design of the shoe does an excellent job of securing and supporting the mid-foot and placing a generous amount of cushioning in this region and this makes for a huge improvement in comfort both in shorter (<15km) and longer (>25km) runs. As a forefoot striker, as I tire my midfoot begins to increasingly make contact coincident with the forefoot and support and cushioning in this area becomes critical for comfort and efficiency. I find the S Lab Sense Ultra to maintain a high level of comfort throughout runs, independent of the state of muscle fatigue and it is apparent that the onset of foot fatigue is pushed further out in time and distance compared to other shoes that I have worn (e.g. Sense, X-Series, Sonic, S Lab Wings, etc.). There is also substantial cushioning in the forefoot and this may be playing a role as well. Of course, the heel is even more cushioned and this is very welcome on long (> 3km) steep downhills that are typical here in the Northern Rockies (as well as in the Alps, where the  steeps are truly steep!). Combined with the excellent proprioception, bombing downhills in these shoes is a real pleasure and even at this early stage in transitioning from skiing I am finding some significant improvements in downhill speed.

The Sense Ultra also have very good glissading capabilities. It is not clear why but these shoes will glissade down a steep snowfield with significantly more control than I have experienced in other S Lab products. I suspect that the lug design is playing a role since the diamond shapes are oriented in way such that they may be providing a certain amount of directional stability. As a cross country skier I am intimately familiar with and comfortable on a narrow platform and the control on snow with the Sense Ultra is something like what a ski feels like, albeit minimally. I have much more control in these shoes on long glissades and this has been a welcome feature of the design given the amount of snowfield running I have been doing.

After about 300 kms, there is hardly any noticeable wear on the outsole, no excessive wear on the uppers (even though I have postholed through a fair share of crusted snow fields where abrasion is very high), and no noticeable reduction in cushioning. If there is a potential issue it might be the fact that the upper on the medial top of the right foot has a “wrinkle” that could develop into a high stress site and eventually a hole.

A “wrinkle” has formed on the right shoe on the medial top of the upper mesh fabric and may eventually lead to a hole at this higher stress spot. Only time will tell.

The “wrinkle” is not present on the left shoe so this is probably some sort of manufacturing issue. Whether it is common or not, only reports from other users will confirm. If my experience holds in observations of other such high stress spots in upper materials there will likely be a hole here at some point- the question is when.


The Salomon S Lab Sense Ultra is an excellent shoe for just about any terrain or condition one might experience. The midfoot support and overall cushioning along with excellent proprioception, grip, and acceptable weight lead to a “sweet spot” product for the trails. This will clearly be my go-to shoe for the 2017 trail running season for both training and competition. Stay tuned for another update- probably at around 700 km when I will have a lot more time/distance on the shoe in technical terrain.


Salomon Sense Pro Max – an Improved Pro Pulse and a Trail-Worthy Cushioned Option

In August of 2015, Salomon introduced their first truly “cushioned” shoe, the Sense Pro Pulse. I reviewed that shoe and summarized it as follows:

"Salomon fit with Hoka Clifton cushioning at Stinson weight. 
Life is compromise!"

Lamenting the 335 gm weight of the Pro Pulse did not prevent me from using the shoe extensively in hill bounding and other higher impact activities as I worked through an intensive cross country ski training regimen last Summer and Fall. Shoe fit is key in successfully executing upon this type of “agility+power” workout and the Salomon fit technologies (EndoFit, SensiFit, and QuickLace) make all the difference. Other cushioned shoes that I have tried have marginal-to-bad fit and this combined with the large stack heights make the shoes a dangerous choice for these workouts that require significant off-axis force vector stability. I found the Pro Pulse to have sufficient grip for the mostly steep (20-30% grade) and super steep (>40% grade) “dirt roads” that made up the staple of the hill bounding workouts. I also found that the cushion was essential for my 60 yo connective tissue to accommodate an elite-level of training stimulus in cross country skiing-specific sessions that include significant high impact repetitions (e.g. hill bounding, plyos, and other “agility+power” exercises). The Sense Pro Pulse shoes were “enabling” for my ski training schedule.

I was pleased to see Salomon announce the Sense Pro Max as a Pro Pulse replacement last summer with a shoe that is slightly lighter (276 gms for my US 7.5/ EU 40 2/3 or 18% lighter than the Pro Pulse) but with a much more aggressive outsole and some new dampening technology that will be described below.

I received a pair of Sense Pro Max in early February and have put only about 20 miles (30 km) on them- we are currently in the middle of an epic snow year (20+ feet and counting) and my current focus is on competing at the World Masters Cross Country Skiing Championships in early March (see elsewhere on this blog). But I did want to try these shoes out and get a better understanding of the design approach and execution. What follows is a “first impression” look at the Pro Max and I will follow-up with updates as usual.


Salomon Sense Pro Max includes new midsole dampening technology called “Vibe” that utilizes “Opal” dampening inserts placed in the forefoot and heel in cavities in the Energy Cell+ EVA midsole material.


The Sense Pro Max has a much reduced “rocker” profile when compared to the Sense Pro Pulse model that it is replacing. Although the forefoot still has a significant upward curve, the midfoot to heel is nearly flat to the ground. It is not clear why Salomon have made this change but I will assume it was based on testing by and input from their athletes.


The Salomon Sense Pro Max has a reduced “rocker” profile when compared to the Sense Pro Pulse that it replaces. This profile is in contrast to many other highly cushioned shoes most of which have a very prominent “rocker” profile.


The Sense Pro Pulse from 2015 had a very prominent “rocker” profile typical of highly cushioned shoes.

All of the Salomon fit technologies are present including Endofit (a separate inner sock-like element engaging the foot), Sensifit (outer polymer overlays integrated with the QuickLace system), and the QuickLace system. The tongue is minimally cushioned.

The shoe is quite flexible for such a cushioned construction but still includes the Salomon ProFeel film technology that provides protection from rocks, etc. Salomon have figured out how to design with the ProFeel film and yet yield flexible constructions that still give significant rock protection along with better trail/road proprioception. Such improved proprioception is one of the factors that distinguish the Pro Max (and the previous Pro Pulse model) from many other highly cushioned shoes.

As mentioned above, my size US 7.5 (40 2/3 EUR) weigh in at 276 gms (9.7 oz) which is getting close to the weight range for a racing shoe. This shoe is not a Salomon racing product as it is intended for general training and trail running. Note: It appears that Salomon have dropped the “CityTrail” concept that the Pro Max predecessor was part of but was never well explained by the company. The Pro Pulse was a part of the “City Trail” group but the Pro Max has a much more aggresive outsole more intended for rougher trail use.


The Sense Pro Max midsole has a number of new technology features, the most prominent being two dampening elements that are inserted into the midsole at the forefoot and heel. The primary midsole material is Energy Cell+, a dual density EVA that is compression molded in a way that achieves firmness in some sections and a softer feel in others. The new dampening elements are called “Opal” and these (approximately 75mm X 100mm X 15mm thick- forefoot and 50mm X 50mm X 15mm thick- heel) “pucks” are inserted in cavities in the top of the midsole at the interface with the footbed. Here’s how Salomon describes the Opal material:

Opal is a cushioning compound that is inserted into the midsole that
provides a soft and comfortable underfoot ride with the benefit of
high-rebound. Cushioned and bouncy, the best of both worlds. In 
addition, Opal is extremely lightweight, durable and maintains its
performance in extreme temperatures.

Looking into this a bit more, it appears that the Salomon Opal material is a low density open cell foamed polypropylene (PP) with the possible addition of butyl rubber.  The known high mechanical dampening properties of certain PP compositions combined with significant open cell void space seems to allow for a unique combination of properties for use in running shoes.


The Salomon “Vibe” dampening technology includes a proprietary midsole insert material called “Opal” that is claimed to reduce mechanical vibrations imparted to the runner.

The combination of the Energy Cell EVA and the Opal inserts makes up what Salomon call the “Vibe” technology that is being used in a number of 2017 Salomon models. It is claimed that this technology significantly reduces mechanical vibrations imparted to the runner during footstrike. These vibrations are thought to reduce the efficiency of running, increase muscle fatigue, and lead to connective tissue and muscle damage. Sounds like another “Holy Grail” of technology that is able to mitigate the most detrimental mechanical forces and impulses in running- we shall see.

The other models that offer the Vibe approach are in the road-specific shoe line and include the S Lab Sonic 2, Sonic Pro 2, and Sonic. The Vibe technology and initial impressions reviews of the road shoes is nicely summarized here and more specifically, here. I will not be reviewing or using any of these road shoes as they all have traditional laces- something that I have no interest in putting up with particularly when the speed laces work so well, are lighter, are less prone to absorption of moisture, and make putting on and taking off the shoes quick and easy.

Of course the Pro Max is a highly cushioned shoe (at least for Salomon) and the stack heights are the same as were extant in the Pro Pulse and consist of a 30 mm (heel), 24 mm (forefoot) stack with a 6mm drop. Add about 3mm to total stack heights to include the outsole.


The upper is a very breathable (maybe too breathable) 3-D knit mesh. The entire upper is quite cool and drains water well as I found out whist running during a brief melt-out and the trails, roads, and walkways were flooded with up to 6″ of water. I expect that this material dries fairly quickly, at least in the low humidity conditions typical here in the Northern Rocky Mountains, but only testing will tell. The upper mesh seems like it may be too “open” and allow significant fine dust to accumulate inside the shoe. This will be obvious once I out some miles on these on dry dirt- stay tuned.


The toe bumper looks to be sufficient for rocky trail running and the polymer toe overlay looks thin but needs to tested to see how well it protects.

The ankle cup is symmetric and there is a stiff structure around the ankle cup and heel. A solid polymer element is integrated into the back of the heel. A continuous, but very minimal polymer overlayer stretches across the toe area and a reasonable toe bumper sufficient for trail use are present.


The typical Salomon rigid construction and symmetric heel cup are utilized on the Pro max.


Other than the new Opal dampening technology, the other big change in the Pro Max relative to the Pro Pulse is the outsole. Salomon have totally redesgned the outsole and made it much more aggressive and suitable to a wide variety of trail types. The aggressive outsole will, however, limit the amount of running you might want to do on roads with this shoe.


Perhaps the biggest change in this shoe from the Pro Pusle is the much more aggressive outsole that is clearly intended for use on rugged and rocky tails.

The mostly diamond-shaped lugs include isolated elements as well as overlapping “echelon” groupings. I have only had this shoe on snow, wet snow, and wet pavement so mud performance will be documented in an update after I get more miles in the dirt and muddy trails.
Salomon have narrowed the outsole planting width at both the forefoot and the heel when compared to the Pro Pulse. In size 7.5 US/ 40 2/3 EU, the Pro Max is 103 mm at the forefoot and 93 mm at the heel whereas the Pro Pulse was 105 mm and 95 mm. The Pro max also looks and feels narrower although it did not affect the comfort for me. The shoe is very comfortable.
The outsole composition is the “Wet Grip” ContraGrip material that Salomon started using in the S Lab XA Alpine shoes introduced over the summer. This material has very good grip in wet conditions on hard surfaces, submerged algae-covered rocks and logs, and on snow and ice.
running performance

With very limited miles my first impressions of this shoe are mixed. They definitely feel nicely cushioned and the fit technologies give a very good sense of control on firm and loose surfaces even with the large stack heights. The more aggressive outsole is a welcome addition as the grip on the snow, wet snow, and wet pavement that I have been on is much superior to the Pro Pulse and more in line with the S Lab Sense Ultra and S Lab XA Alpine shoes. These shoes look to be a Pro Pulse that is fully intended for rugged trail use.

I have not noticed any reduction in mechanical vibrations compared to the Pro Pulse or even the S Lab Sense Ultra but, with such limited miles, I will defer any assessment at this point.


The lower weight is also noticeable right away and will be a nice feature for the hillbounding sessions that I intend to do with these shoes. The exaggerated above ground movements of the foot in hillbounding can be highly affected by an overly heavy shoe. The Pro Pulse was right on the edge of being too heavy so the Pro Max should work out well.

On the downside, I can very much feel the “Opal” inserts under the forefoot and they give a sort of uneven, disconcerting feel during footstrike. Perhaps with use this will fade away but right now it detracts from the running experience.

I’ll be putting more miles on these but probably not in the near future as we will likely be skiing well into May this year. An update will come a bit later than usual.


$150US. In line with other highly cushioned trail shoe offerings, but this one has great fit, good proprioception, and some new (unproven) dampening technology. All of which is likely worth the minimal added cost.

bottom line

A premium fit, trail-worthy, highly cushioned, “almost-racing-weight” trail shoe with dampening technology from Salomon.

The Road to Klosters – Race Course Profiles, Peaking, and Training Update

klosters logo

This is Part 8 in a series of posts about training and preparation for the World Masters Cross Country Skiing Championships in Klosters Switzerland in early March 2017. See Parts 1, 2, 3, 4, 5, 6, and 7 for an overview, specific training plans, strength training, an evaluation of the required pace to podium in the M07 and F06 age classes, critical assessment of the efficacy of Block Periodization, fleet evaluation, and racing weight, respectively.

Training for any event should include some race-specific sessions that will simulate what one will see on race day. Since cross country skiing competition dynamics are significantly driven by the details of the race course terrain, it is important to establish an understanding of the race course profiles, climb sequencing, and downhill challenges to both simulate racing but also to develop pacing strategies. This analysis all starts with elevation/distance data for the race courses.

The MCW Klosters website has .pdfs of each of the race courses that will likely be used at the events. I say likely because there could be last minute course changes due to weather and conditions at the time of the races. The resolution of the .pdf files is marginal and with 60 year old eyes, getting accurate and precise elevation/distance data from the files is a challenge.

I contacted the race organizers in Klosters and asked if they had the digital gps files that were used to construct the .pdfs on the website. The person I contacted responded promptly and wanted to know what I would do with such data and I told her that I would use the data to have an accurate digital file of the profiles so I could make comparisons with the trails here in Sun Valley. I suggested that there should be digital files of the courses since they would be needed to produce the .pdfs on the website. I further suggested that it would be productive if the organization could make the .gpx or .tcx files  for the courses available (or whatever digital files they used to make the .pdfs) so the competitors could have an accurate representation  of the profiles. I indicated that the Chief of Course might have access to the files. Unfortunately, I have never heard back from the race organization. So what follows has been derived optically from the website .pdfs and, as such, will have some errors and be of lower resolution that typical digital data. However, the profiles presented here will be representative and largely applicable to any comparison exercise.

klosters world masters course profiles

There are four courses that will be used at Klosters-

  1. Doggiloch – an easy “geezer” 5 km couse for the M10-M12 and F09-F12
  2. Aeuja – the 5km relay course for M01-M09 and F01-F08
  3. Schwaderloch – a 10 km course for the distances races for M01-M09 and F1-F08
  4. Schindel Boden – a 15 km course for the distance races for M01-M09 and F01-F08

I did my best to translate the elevation/distance data from the website .pdfs and made some .xls files that could be plotted with comparison courses that are available here in Sun Valley. The data are presented in “normailzed elevation” form* to facilitate comparisons. Distances are in km and elevation is in feet. Sorry for the mixed units but I am helping some fellow competitors here in Sun Valley (USA) and they are most comfortable with elevation expressed in feet.  Peak actual elevations (in feet) are noted where appropriate.



I will not comment on the “geezer” 5km course but the Aeuja 5km relay course would appear to have a “crux”, nearly continuous, 170 ft climb starting at about 1km and ending at about 2.75km. This climb should do a reasonable job of spreading the teams out but it could also lead to some very hard individual efforts to keep teams in contention- should be exciting to participate and watch!

The Schwaderloch 10 km course is the same as the relay course for about the first 3km and then begins to climb a second and third time to a peak elevation of 4179 feet. Likewise the Schindel Boden 15km course is the the same as the Schwaderloch 10km course for about the first 9km (to about the highest point on the Scwaderloch course) and then continues to climb steeply to a peak elevation of 4267 feet before descending back to the start through a few small hills.

Although possible, it is difficult to get a feel for a course just from the elevation profile so it is informative to plot a race course along with a local training loop at one’s home area. From such a comparison one can evaluate the steepness of the climbs and descents, the lengths of the flat sections, and the sequencing of the course challenges. Plotted below are comparisons of the Schwaderloch 10km course with a loop at the Sun Valley Nordic Center, known as the White Clouds-DiamondBack Loop and the Schindel Boden 15km loop with another loop at the Sun Valley Nordic Center known as the Trail Creek-Boundary-Proctor-SideWinder Loop.


As can be seen, the net elevation change and absolute magnitude of total elevation change are comparable with the Klosters courses having a bit more corrugation (short ups and downs). However, there is nothing in the Klosters courses that is as steep as some of the climbs in Sun Valley with the possible exception of the last 75 feet of ascent on the climb to the high point on the Schindel Boden course. None of the Klosters climbs are as long as a number of the climbs in Sun Valley. With the exception of the super fast descent off of DiamondBack, the downhills are quite comparable. The Klosters courses are also about 2000 feet lower in absolute elevation.

This analysis enables one to do some simulations and familiarization of the Klosters courses on one’s home trails. In our case, the TC-Boundary-Proctor-SideWinder-TC loop is a good proxy for the Schindel Boden course from both a total elevation change perspective and in steepness/length of climb (the SideWinder climbs are very similar to the steepest parts of the Schindel Boden course).

Another functional comparison is the Schwaderloch 10km with the 7.5 km Lake Creek Loop in Sun Valley. The Lake Creek trails are the primary trails that the local nordic team trains on, including the National-level athletes. It has a big mix of terrain and a stadium area where competitions are staged. Nearly all of the climbs at Lake Creek are as steep as or steeper than those on the Scwaderloch course but the climb lengths are similar and the total elevation gain is similar. In a different way, the Lake Creek Loop is also a good proxy for what we will see in Klosters.


Another analysis is to look at elevation/distance data for some interval loops and hills that one does regularly and then compare to the race courses. One interval hill we use regularly is a steady climb that takes about 6-7 minutes, depending on effort level and conditions. This hill is plotted below along with the Schwaderloch course. The ascent grade of this hill is the same as the grade in the start of all of the courses out of the stadium area at Klosters. Given that I use the local hill as a double pole workout, it looks like I will be double poling for at least the first 4 km in the classic races (and all of Aeuja 5km relay course)- and probably 80% of the rest of both the Schwaderloch and Schindel Boden courses as well. I’ll need to consider going without kick wax, or maybe going with skate skis and combi boots.


A local interval climb vs the Schwaderloch course. The interval is done as a double poling workout- looks like much of both the Schwaderloch and Schindel Boden courses will be double pole in the classic races! But we will have to wait until we get there to ground truth and confirm.

Of course there is no substitute for training on the real courses and I am certain we will be surprised by something once we get to Klosters, but it is worth the effort to develop some level of feel for the race courses prior to arrival.


As any experienced endurance athlete will know, developing a robust peaking program for an “A” race is critically important. Young athletes have great difficulty with this because takes time to discover the type of peaking progression that works best. And “best” is a very individual thing, a thing that requires some experimentation. Having been active in competitive endurance sport for over 40 years, Team Bumble Bee has pretty much figured out what type of peaking program works for us as individuals. Given that we are both “high responders” to interval training, our peaking program is tailored around this advantage. Without going into the details (as it is highly individual and not reliably transferable to others) the basic program includes the following steps:

  1. cut training volume about 4 weeks out from the “A” race and
  2. increase the intensity until about 10 days out from the “A” race, then
  3. cut both intensity and volume for those last 10 days
  4. focus on being fully rested as we are seated on the plane to Europe
  5. minimize interactions with others and wash hands regularly
  6. glue your feet to the floor

Team Bumble Bee is now well into the increased intensity portion of the program where we are doing intervals every other day until about 21 February. Then everything is easy skiing and resting until we toe the line at the first race. This program has worked well in the past so we are going with it for the World Masters.


Bee finishing up a VO2 max fartlek-style interval session with a smile- we love intervals!!

training update

In part 7 of his series I put a goal in place to add weight- a lot of weight, like 8 lbs or 6% of my then extant body weight of 128 lbs. This goal came about after an analysis of the racing weight of competitive cross country skiers summarized in the part 7 post. I realized from this analysis that I am way underweight for a competitive skier and that my performance is likely being negatively affected. Adding 8 lbs would just get me onto the charts for the competitive athlete group of my height- but this 8 lbs cannot be fat, it must be lean muscle mass.

So I continued the strength progression program rather than going into “maintenance” mode as planned. I also upped calorie intake by about 500-700 calories per day (20-25% increase) whilst ensuring that protein levels were more than sufficient. What happened? Well, I gained just 2 lbs in six weeks but I also became even leaner, reducing body fat from about 8% to about 6%. Though I succeeded in adding lean muscle mass, the rate at which this can happen (for me anyway) is too low to allow the original goal to be achieved in the timeframe that I have. But I am stronger and I can feel additional power on skis so it would seem that I have done what can be done in the time allotted and I will just have to play those cards at the Wolrd Masters races. However, I will continue the program for increased weight (in the form of lean muscle mass) after a short hiatus from the strength work for the competitions in Klosters.

I also had the opportunity to work on technique with a couple of current World Cup skiers and it was very valuable. We worked on double pole and V2, did some video, and had some longish skiing together. I managed to put some tweaks in place that have led to increased power and efficiency.

Overall the training has gone well with no injuries or chronic issues other than a minor hip flexor strain (while shoveling the copious amounts of snow that have come down this year). It took about a week to come fully back but the strain occurred just before a rest week where I was slated to do a bunch of ski testing and feeding during a race, so there was no real set-back.


Near-record snows in the Sun Valley area has led to great training and racing conditions… yet we still hear people complaining here- #getalife!!

The two per week interval sessions have been very high quality and the results are obvious. Hopefully that continues in this last stretch of interval work concentration in the peak progression.

Downhill skills have also improved although this is still a weakness and one that I continue to focus on in every workout. I have found “my edges”- both on the skis and in my current skills. Most of the work is in proper body position and I am slowly getting there- but not without some scary moments!


Bumble testing his ski skills on a fast downhill turn!

travel and travel stress

Travel to an international venue can be very stressful, perhaps even more so than a lot of one’s training. Therefore it is important to manage this stress and minimize the impact it might have on your performance. Everyone is different but what works for me is to consciously go from “control freak” mode that works well for day-to-day training to a much more relaxed “whatever happens happens” mode whilst traveling. You cannot, in any real way, take much control over what happens once you are in the “transportation channel” so it is best to concentrate on relaxing as much as possible and making good decisions along the way. So, put some time buffers into the travel schedule, take some reading, some headphones, and take an interest in watching what’s happening around you to make the best of a fundamentally stressful time.


We are taking 8-10 pairs of skis, 8 pairs of poles, and four pair of boots so packing is going to be a challenge. If I have time I will put up a post about how we managed to get everything into suitable ski bags and carry-ons… and within the weight restrictions.

final thoughts

It’s been nine months of concentrated and focused training for the Klosters World Championships. There have been significant gains in VO2 max, LT pace, max strength, and power on skis. I’ve learned that even a 60 yo can do “elite-level” training both with respect to volume and intensity- albeit at a slightly slower pace and with significantly reduced accelerations. Averaging in excess of 15h of “certified” training per week with peak volume at 24h on a diet of blocks of intensity and endurance follwed by a more traditional race season structure convinces me that there might be yet another, even higher, level to which this training can be taken.

As far as the efficacy of the “block periodization” approach, we will have to see as the results come to fruition at Klosters. I certainly enjoyed the “block” approach as it allows one to focus on a singular aspect, fully develop that ability, and then move on. Bringing it all together for the race season has gone smoothly from a cardio, strength,  and endurance perspective as my position in races has been right there with former top National performers and retired Olympians that make up the competitive group in the citizen races. My biggest challenge- sticking with the lead pack on the technical downhills… I’m getting there but there is still work to do.

I will write up a full training analysis after the World Masters, but I feel very fit, well rested, and ready to attack the starts and accelerate on the climbs- hopefully with good results!

*the elevation data are transformed to reflect a starting elevation of zero feet

Salomon S Lab Sense Ultra 2017 – X-Series With a More Aggressive Outsole

Note 20 June 2017: Salomon have just announced the S Lab Sense Ultra 2 which is said to be available Spring 2018 (likely in Jan/Feb 2018). The new version includes more cushioning and a wider last in the midfoot. Salomon have also incorporated some technology from their cross country ski boot designs for skate boots- a stiff plastic element that crosses over the foot just below the ankle and is integrated with the speed lacing. This element is called “Skin Guard” and supposedly allows for better control on descents. Although not as adjustable as the ski boot equivalent, the “Skin Guard” looks like it might be an interesting development. Unfortunately, the shoe is now heavier at 300 gms for size 9 (US). Pictures and brief description here.

I have provided 300 km and 1200 km updates on this shoe.


Last summer Salomon announced that they were splitting up the S Lab Sense line to include two product branches- the “traditional” low drop, low cushion, “Kilian” shoe and a new product branch specifically for those runners who desire a bit more cushion and mid-foot support. The “traditional” shoes are continuing the evolution of the S Lab Sense line with the S Lab Sense 6 and S Lab Sense 6SG models.


Salomon S Lab Sense Ultra for 2017. A new model and a new direction for the S Lab Sense product line. A direct replacement for the S Lab Wings? Possibly.

The new line of cushier shoes is called the S Lab Sense Ultra. Although the “ultra” designation has been used in the S Lab Sense line previously, this shoe is clearly designed for the demands of longer distance ultra trail use. But the differences in this shoe with the rest of the S Lab Sense line for 2017 are numerous and truly make the S Lab Sense Ultra a quite separate entity.

The question has come up in the comments as to whether the Sense Ultra is a direct replacement for the S Lab Wings 8. Although the Wings 8 is still in the SS 2017 line-up for Salomon it may have a short life. The Wings 8 is definitely a different shoe but the crossover with the Sense Ultra is so substantial it seems to lead to quite a bit of duplication at this point; we shall see.


A reversed color scheme for the Sense Ultra from the rest of the S Lab Sense line is distinctive.


The S Lab Sense Ultra for 2017 has a reversed color scheme from the rest of the S Lab Sense line with a black body and a red heel (compared to the red body and a white (Sense) or black (Sense SG) heel). The new S Lab graphic is also in evidence. Sensibly (pun intended), speed laces and a lace pocket are included.

All of the industry-leading Salomon fit technologies are incorporated including EndoFit, SensiFit, and OS Tendon. These fit technologies are the basis of what makes Salomon shoes such high performers.


The Sense Ultra has a substantial toe bumper and (thank the heavens!) speed laces and a lace pocket.

Beyond colors, there are quite a few features that differentiate the S Lab Sense Ultra from the S Lab Sense starting with the significantly thicker toe bumper and what appear to be heftier materials in some of the overlays and the tongue. The tongue is also more padded than in the S Lab Sense, presumably to allow for additional comfort at long distances. For me, such long distance comfort has been an issue with the S Lab Sense line and I switched to the much more comfortable (and supportive) S Lab X-Series and S Lab Sonic for ultra distance races. I still will do 10 km to 30 km rugged mountain trail races and runs in the S Lab Sense however; the superior trail feel at higher paces is important. But if the race trails are buffed I will still use the X-Series/Sonic even at the shorter distances since these shoes are about the same weight as the S Lab Sense but have a larger outsole area with a less aggressive lug set-up, both of which can positively affect pace in smoother conditions.


A trim but not too narrow silhouette looks to be a good fit for D-width feet. Wider feet may want to look elsewhere.

The toebox of the Sense Ultra is slightly narrower than the X-Series/Sonic but not as narrow as the S Lab Sense 5 (I have not examined the Sense 6 yet). The polymer overlays have the same pattern as recent editions. The mesh used in the upper forefoot and medial/lateral midfoot is also the familiar material that Salomon has been using in the Sense line for the past couple of years. The polymer overlay at the toe comes up a fair distance onto the top of the forefoot and also up the lateral and medial midfoot to protect this mesh from wear-out in high stress/high abrasion areas. Such mesh wear-out was problem with early editions of the S Lab Sense.


The heel area has the familiar beefy and stiff, symmetric construction used in the Sense line for years. The heel counter is nicely padded and rolls over the top edge and down a bit. The liner material in this area appears to be a bit “loose” (see plan view photo above) but once the shoe is on there is no extra material being bunched up. This heel liner material is the one area on the X-Series/Sonic that actually wears. I have worn holes in the material after about 500 km but the wear does not adversely affect the comfort or performance of the shoe. Based on the construction here I expect this sort of wear will be seen on the Sense Ultra- but only time will tell.


The midsole is where the largest differences between the Sense and the Sense Ultra lie. All models utilize the “Dual Density” EVA compound that has been used in this line for a while but that is where the similarities end. First, the Sense Ultra has a drop of 9mm compared to the 4mm drop of the Sense 6- this is a big difference.  Second the cushioning in the Sense Ultra is much increased over the Sense. With a 25mm heel and a 16mm forefoot the Sense Ultra stands in a different category when compared to the 18mm heel and a 14mm forefoot of the Sense 6.  This is a substantial difference in midsole thickness, particularly in the heel. All of the Sense models have been increasing midsole thickness over the past few years indicating that even the Salomon athletes have been pushing to get a bit more comfort out of the Sense. But the Sense Ultra has taken this cushioning to new level. The 2017 Sonic 2 also has similar degree of thicker  cushioning as the Sense Ultra, but actually offers another mm of cushioning at the forefoot. A review of the Sonic 2 is forthcoming.

Both the higher drop and thicker midsole lead to increased comfort. The higher drop gives substantial midfoot support that is highly appreciated the longer a race (or run) is. The added cushioning in the Sense Ultra should not only give a cushier ride in general but also allow for speedier descents (particularly in buffed terrain) and give some reprieve for inattention to sharp rocks and other features known to lead to foot bruising. While running, the added cushioning is most notable in the heel  as will be addressed below.

Also new in this model are the Hoka-like lateral and medial chassis supports that approach the mid-plane of the shoe. This support system can help highly cushioned shoes from being too tippy- something that many runners have complained about for years in “maximal” shoe designs.


The outsole of the Sense Ultra is of a new design pattern not seen previously. The pattern is asymmetric and is made up of sparsely arranged diamond shaped lugs with a substantial (3mm) depth. The outsole is purely trail specific and you will want to limit the number miles on pavement. The compound is Salomon’s Premium Wet Grip ContraGrip material and this outsole should perform just as outstandingly as it does on the S Lab XA Alpine shoes reviewed earlier.


A new outsole lug shape and pattern looks to be a good mud performer- but mud performance needs to be done on all of the variants to truly evaluate the performance. Given the epic snow year here in the central Idaho mountains, we will likely have an epic mud season as well!

The ProFeel TPU film rock protection is included, as expected and, combined with the added midsole cushioning, should make these shoes pretty bombproof on even the most technical of terrain. Mud performance will likely be good but this always has to be tested in the various types of mud as the outsole composition plays a big role in mud adherence. But again, if the mud performance of the XA Alpine is indicative then these shoes will be a good choice in muddy conditions.

running geometry

Historically the S Lab Sense line has been a “flat” and neutral shoe tending toward a minimalist user base. With the introduction of the X-Series in 2015 and continued with the Sonic in 2016, a significant “rocker” geometry is slowly taking hold over many models in the Salomon lineup. This is continued here with the S Lab Sense Ultra where a significant “rocker” is present even to the point of being very much like that seen in Salomon’s “Hoka”-like  Sense Propulse (2016) and Sense ProMax (2017).



Not quite a true “Hoka” rocker but the Sense Ultra sure does have the “rocker” DNA built in. A “rocker” geometry is important with any highly cushioned running shoe.

The “rocker” geometry is an important part of any cushioned shoe since the foot-set deformation at impact into the midsole cushioning leads to a noticeable barrier impeding forward motion. The “rocker” geometry can help overcome this issue by allowing for just a bit more rotation that makes the foot-set deformation less problematic. This geometry also promotes a forefoot-midfoot strike.


The S Lab Sense Ultra shoe is quoted as weighing in at 275 gms (9.7 oz) for a size 9 (US). My size 7.5 (US) (40 2/3 (EU)) tipped the scales at 259 gms ( 9.1 oz). This is substantially heavier than the quoted 218 gm for a size 9 (US) in the Sense 6. So there is no free lunch as all the cushioning and support in the Sense Ultra comes with added weight. Weight matters- a lot, particularly for lighter weight (sub 125 lbs) runners like me. But in long races comfort will trump weight- and some will argue the same for longer training runs. The older I get the more I like comfort and this shoe tips to the side of comfort with a reasonably low weight. Not perfect but getting there.

initial running impressions

It has been an epic snow year here in the  central Idaho mountains- over nine feet of snow and counting. So there is no dirt to test the Sense Ultra on but there is plenty of packed powder trail for running. I’ve had the Sense Ultra out for about 30 km of mixed running including nice packed powder, some ice, and reasonable vert. As expected the fit is superb and the feel is that of a slipper with great grip. Proprioception is excellent and I find the midfoot support to be similar to the X-Series/Sonic.

The added cushioning is immediately noticeable, particularly in the heel and accentuated on downhills. Although cushy, the run feel is not overly so as is the case in so many highly cushioned shoes. The ice performance is very similar to that of the XA Alpine- good grip but one will still need spikes on any icy downhill.

I did one run with a new X-Series on one foot (I stockpiled some X-Series because Salomon put “traditional” laces on the Sonic for 2016) and the Sense Ultra on the other. The Sense Ultra has a slightly more cushioned forefoot but otherwise the feel is the same as the X-Series. The S Lab Sonic 2 (2017) has a similar amount of  cushioning in the heel and what appears to be a bit more cushioning in the forefoot compared to the Sense Ultra. As indicated above, I will be reviewing the S Lab Sonic 2 once we see some pavement and dirt here in Sun Valley. Unfortunately Salomon has continued with the “traditional” laces on the S Lab Sonic 2- a big mistake.

Although I will need many more miles to confirm this, the S Lab Sense Ultra seems to strike a nice balance of cushioning and proprioception much like the X-Series and Sonic. In fact I shall suggest that these shoes are very much a trail-specific X-Series/Sonic- which is exactly what I have been hoping Salomon would produce. The more aggressive outsole of the Sense Ultra will likely handle even the most technical trails from a grip perspective. This means that we might have something here that gets just that much closer to the never attainable, near-perfect ultra trail mountain running shoe.


$180 US. Steep as always, but likely a good value given the usual durability of the S Lab shoes.

bottom line

Finally, a cushioned Sense for the trail with good midfoot support and light(ish) weight. This may be my go-to shoe for the upcoming season. Stay tuned.

Salomon S Lab XA Alpine Shoes – a great hybrid shoe for mountain running adventure

Born out of requests from Salomon athletes for a shoe that would combine the proprioception of an S Lab Sense with the technical terrain capabilities of the S Lab X Alp Carbon GTX, the Salomon designers have created an outstanding hybrid shoe that is likely to find much more use than just off-piste mountain exploration.


The XA Alpine- a shoe that is ready for some high mountain adventuring!


A couple of years ago Salomon, working with Kilian Jornet and other Salomon athletes, developed a “fast and light” alpine shoe with very high mountaineering technical terrain performance- the S Lab X Alp Carbon GTX shoe. This shoe is lightweight for the category (500 gms size US9), has  a Gore Tex upper/gaiter, a unique “carbon edging chassis”, accepts crampons for glacier traverses, and is suitable for lower level alpine climbs- in short a very versatile shoe for playing in places like the high Alps and other such terrain. This shoe, however, is not intended for running nor would running in it be the least bit pleasant primarily due to the stiffness.

Continuing development and testing with athletes that wanted to run (not hike or trek) in places like the high Alps and not be deterred by glacier crossings, Class 3 scrambles, or knife-edge ridge ascents that may be a part of a desired route, the S Lab XA Alpine shoe emerged from the prototype studio in Annecy. This shoe represents a hybrid design from a mash-up of technologies from the S Lab Sense mountain running shoe platform with the S Lab X Alp Carbon mountaineering shoe platform.


The XA Alpine has a distinctive colored graphic on the lower mid-foot to heel area. The gaiter zipper works more smoothly and effortlessly than any other gaiter or boot zipper that I have ever used (including all of the zippers on the Salomon cross country ski boot line).


Starting with the super responsive S Lab Sense running shoe as a basis, a slightly increased drop (from the 4mm of the Sense to 6mm here) is used to increase mid-foot support and a modified “carbon edging chassis” is added to give lateral edge stiffness for scrambling and to allow crampon use whilst still retaining substantial longitudinal flexibility for running comfort. For protection in snow and ice, limited water resistance, and to prevent intrusion of debris inside the shoe, a full-wrap gaiter is employed that includes a water resistant lower half, a highly breathable upper half, and (what appears to be but is not) a waterproof zipper as well as ankle pads and a padded cuff at the upper termination of the gaiter.  There is also a thick rubber toe cap for rock protection.


Plan-view of the XA Alpine shoes showing the water resistant lower part of the gaiter, what appears to be a waterproof zipper, and the breathable upper half of the gaiter (which seems to have a DWR coating). The shoes are not waterproof and water does intrude rather quickly in streams. It seems that the water resistant layer is intended to minimize water intrusion in “wet snow” or “melting snow” types of conditions.

Inside, the foot cavity consists of what appears to be a S Lab Sense upper and footbed- and it definitely feels like the Sense as all of the fit technologies are present (EndoFit, SensiFit, Speed Laces and lace pocket, etc.). Due to constraints from the gaiter structure the shoe is slightly more difficult to get one’s foot into, however, once in, the feel is very much that of an S Lab Sense.


Gaiter unzinpped and pulled back to reveal the inner “shoe” that appears to be a S Lab Sense. The fit is very good as expected from all of the fit technologies included.

This construction of an S Lab Sense upper combined with the lightweight gaiter is grafted onto a deeply lugged outsole that utilizes Salomon’s latest “Premium Wet Traction” ContraGrip rubber compound. The lugs are highly separated to help facilitate responsiveness, grip, and to allow for more efficient mud and snow release.


The outsole utilizes Salomons’ “Premium Wet Traction” ContraGrip compound across the entire surface. This compound is astoundingly good in wet and in typical trail ice conditions- at least compared to the standard ContraGrip.

The outsole also has a specially stiff section in the medial toe area to help with footholds on more difficult scrambles and to allow for secure insertion into snow. Salomon calls this the “climbing zone” and they actually label it on the outsole.


“Climbing Zone” section of the medial toe area.


When you put this shoe on it definitely feels like a S Lab Sense, that is until you start walking around- this is when you immediately realize that there is a much stiffer outsole and chassis underfoot. It is not a “bad” feeling, just different- and different for good reasons:

Where most of us would not take the Sense across any potentially dangerous snow field, glacier, or up a challenging and consequential scramble, the XA Alpine will perform quite well and provide the confidence one needs to proceed safely.

While the chassis stiffness is important for mountain performance, it is not a drastically different feel and one that you will likely get used to quickly, as I did.

One initial issue that I have had is that the gaiter causes rubbing on the top of my middle toes near the foot proper. This was very noticeable on the first run but has become less and less noticeable as I use the shoes. It would seem that the gaiter is “wearing in” as the water resistant layer flexes and forms to the topology of my foot. I also wear super-thin S Lab Sense socks that give no padding whatsoever so wearing a thicker sock might make this rubbing entirely absent.


These US 7.5 (40 2/3 EU) weigh in at 334 gms (11.8 oz). Although heavier than a 7.5 US S Lab Sense Softground (247 gms (8.7 oz)) and noticeable whilst running, the additional mountain performance more than offsets the additional weight. And remember is was not so long ago that a 350 gm trail running shoe was considered a “lightweight racer”!

Initial Running impressions

I have had this shoe out for about a total of 50km of buffed and rocky trail running, off-piste scrambling, snow field crossing (thanks to some snow above 9,000 feet), icy steep trails, and some hill bounding intervals in muddy, wet conditions.

The buffed trail running is definitely compromised from a trail feel and speed perspective (compared to usual running in the X-Series, Sonic, and Wings 8) as the stiff nature of the shoe leans more toward a structured product. However, there is still a reasonable amount of trail feel that allows for pleasant running, although I would not exclusively run in these shoes. On mountain exploration runs where there is significant off piste terrain and possible snow these will be a go-to shoe going forward.


Once the ski season is over and the access clears up a bit next spring, these high ridges are where these shoes will be headed…

The performance is excellent on rocky and more technical trail terrain, dry or wet and is outstanding on off-piste scree, rocky steep ridges, boulder fields, and snow fields, once again dry or wet. The “Premium Wet Traction” ContraGrip really is much better than the standard composition in any wet and slippery conditions. Traction on submersed rocks at stream crossings is as good as anything that I have experienced. One note: drainage of the shoe is limited by the water resistant lower half of the gaiter. I found however that water is “pumped” out as you run.

I have had limited experience with the shoe on ice at this point but, so far, I have been astounded as to how grippy they have been- I have both ascended and descended some steep trails that have become icy with what feels like solid grip. They will eventually let go but since they accept crampons** I would suggest that anyone wanting to cross significant ice (or glaciers) might want to consider using crampons. It is not obvious why this compound would be so superior to the standard ContraGrip but there are basically three ways to get better grip in wet conditions and on ice- increased surface area, low-Tg rubber, and nano-sized particulates with sharp asperities. Based on a brief perusal of the recent patent literature all of the approaches are used by various manufacturers singularly or in combination. However, if one is to believe the data in some patents, it seems that the nano-sized sharp particulates are the key to increased grip in wet and icy conditions. I am not sure if the “Premium Wet Grip” ContraGrip outsole has the particulates though. But if it does, the grip should last if the compound has a uniform distribution of the particles throughout the thickness. If it is a surface layer only then there might be some decrease in performance with wear. Only time will tell.

I have had good performance in mud- both sandy aggregate and clay types with good grip and mud release. Much superior to the Sense. A couple of Class 3 scrambles have gone well including one that has been a bit edgy on past ascents/descents using the Sense- much more secure and confident with the XA Alpine.

If you want to see what the XA Alpine can really do on the feet of someone who knows what they are doing, then read Kilian’s post about the 7 summits of Romsdal where he tackles a difficult 24 hour traverse across the mountains in that part of Norway. He does these ascents (and, more importantly, descents) with nothing other than the XA Alpine and a prototype super lightweight ice axe. It is a great read and the video below shows some of the terrain.

For winter running on packed powder these shoes will be fine without any additional traction devices, but on ice I always go with carbide studs of some sort- either imbedded as in the SnowCross and SpikeCross or with an added and removable “mini crampon”, of which there are many varieties that will work well with the XA Alpine shoe. According to Salomon the XA Alpine is compatible with some “real” crampon models but they do not say which ones**. This is a good thing because it will allow for pursuit of mountain adventures that include significant ice.


$250 US. A bit on the pricey side but this is a unique shoe with a lot of technology and sophisticated design elements that are enabling for the new sport of “Alpinrunning“. There are, to my knowledge, no existing competitor products in this category. Based on functionality alone I find the shoe to be a good value if you are serious about getting out into (and back from) the areas you have always pointed at and said “We should go over there and bag those peaks.”

bottom line

A high performance hybrid mountaineering-running shoe capable of going “fast and light” through highly varied terrain from buffed trail to Class 3 scramble ascents/descents to snow fields- and, apparently, with an ice axe in the hands of an experienced user, across real ice terrain. This shoe is the first true “Alpinrunning”-specific product and it is highly recommended for those that want to do some challenging mountain adventuring.

I intend to use these shoes throughout the winter for limited running, for the to-and-fro to skiing, and hopefully for some mountain adventures. I will post updates.


** Update 13 Nov 2016: I came across another recent review of the XA Alpine where an experienced mountain runner/explorer and  shoe reviewer has essentially the same experience that I have had with the shoe. Additionally, this reviewer has tried out numerous crampon options and found many of these to integrate nicely with the XA Alpine. This further confirms the fact that this shoe will be a go-to high alpine running/exploring option for anyone comfortable in that terrain. See the review here:

Salomon S Lab XA Alpine Review – All Mountain, Any Mountain, All Conditions