Salomon announced the Sense Propulse (and the slightly cheaper, slightly heavier Sense Pulse) earlier this year. The highly cushioned shoe, as described in the press release, sounded a lot like yet another Hoka-like offering from a brand that has, in the past, eschewed this highly cushioned trend in running shoes. In fact this shoe perhaps represents a bit of a “mea culpa” for Salomon since the founders of Hoka (Nicolas Mermoud and Jean-Luc Diard) were designers/executives with Salomon when Salomon chose not to pursue their design path toward maximum cushioned shoes. They left the company and started Hoka– the rest is obvious to even the casual observer.
So what does Salomon have to offer in the increasingly crowded field of highly cushioned running shoes? Well, in one word- EndoFit. As you may be aware, Salomon brought a new construction technology to trail running shoes with the Sense line (initially in the S Lab Sense (Gen I)). The construction is called “EndoFit” by Salomon and involves a separate, inner sock-like layer under the upper that snugly engages with one’s foot and produces one of the most (and, if not, the most) comfortable high performance trail shoe fitting systems currently available. Reviews of the Salomon EndoFit construction across the trail running community are nearly unanimous with respect to the superiority of the design. The combination of EndoFit with higher cushioning leads to a quite pleasant experience as will be detailed below.
My shoe closet is littered with numerous Hoka and Altra shoes that have just not worked for me*. The origin of my dislike of the shoes is in the lack of a stable and secure engagement of the shoe with my foot thereby leading to deficient trail performance in the form of a loose platform on top of a mushy midsole. Lateral movement vectors combined with even semi-technical trails is a recipe for inefficient and, at times, sketchy response. Proprioception is marginal at best. Add to this the increasingly reported “knee issues” with highly cushioned shoes and these combined factors have led to my shying away from the maximialist movement. I note that being 5’7″, 125 lbs, with about 7% body fat may not translate well to the use of such maximalist running shoes. At this “low end” weight range I can definitely feel that, independent of the poor engagement with the shoe, I am floating and moving laterally well above the outsole. This may be due to insufficient deflection of the midsole EVA which could potentially lead to a deficient “set” into the shoe. I have not seen any data on the elastic properties of the EVA compound that is being utilized but I know that these properties are non-linear and highly strain rate sensitive, so there may be a materials-based reason for my experience. A heavier runner might have an entirely different experience (more “set” and stiffer material response due to higher strain rates) so please keep that in mind when reading this review. However, for me, the ride is better in the Sense Propulse when compared to the other highly cushioned shoes I have tried; details follow.
I have put about 50 km on the Sense Propulse mostly on trail with some road running as well so these are initial impressions and I will follow up with updates as usual.
Overall the Propulse has a significant “rocker” geometry very much like that seen on many Hoka models. The “rocker” promotes a forefoot stride, helps with toe-off, and prevents the highly cushioned forefoot from impeding forward movement. These are all things that Hoka brought to the market years ago, so nothing new or different here.
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. A removable Ortholite sock liner is also present.
The shoe is quite flexible for such a cushioned construction which is partly enabled by the use of the Salomon ProFeel film technology that provides protection from rocks, etc. The ProFeel film allows for thinner and more flexible constructions whilst still giving significant rock protection and better trail/road proprioception. Such improved proprioception is one of the factors that distinguish the Propulse from many other highly cushioned shoes.
These size US 7.5 (40 2/3 EUR) weigh in at 335 gms (11.8 oz) which is on the high end of weight for a racing shoe. This shoe is not a Salomon racing product as it is intended for general training and road/trail running in the “CityTrail” concept that Salomon is currently pushing. See Salomon for further explanation of what “CityTrail” means as it seems rather artificial to me…. nor does the concept make much sense either.
The Propulse midsole consists of a 30 mm (heel), 24 mm (forefoot) stack. This is provided via a dual density EVA midsole arrangement where a compression molded EVA element runs the length of the shoe and cushier injected EVA is used in cavities in the forefoot. This provides additional cushioning in the forefoot without increasing the stack height. The stack height is similar to a Hoka Clifton but the Sense Propulse comes in at a significantly greater weight (335 gms vs. the Clifton’s 212 gms for the same US size 7.5 equivalent).
The upper is a very breathable hexagonal knit outer mesh bonded to a denser very thin inner layer. The entire upper is quite cool and drains water well and therefore dries fairly quickly, at least in the low humidity conditions typical here in the Northern Rocky Mountains.
The ankle cup is symmetric and there is stiff structure around the ankle cup and heel. A solid polymer element is integrated into the back of the heel. A continuous polymer overlay across the toe area and a robust toe bumper are present.
The outsole of the Propulse is made from Salomon’s proprietary “ContraGrip” rubber material with an array of three-pronged asterisk-like grip topology features. A much smaller version of this pattern is used in portions of the outsole of the S Lab X-Series. A smoother, higher wear, carbon rubber heel (rubber with imbedded particulate carbon that significantly increases the toughness of the material). The outsole is, in a general sense, very similar to that of the original Hoka Stinson EVO.
Outsole Planting Area
One of the primary design elements in many of the current highly cushioned running shoe options is a significantly increased outsole planting area. Hoka found that a combination of high cushioning with a larger planting area lead to the best running experience for such designs. Salomon have followed suit with the Propulse as the outsole area is much larger than any of their other running shoe offerings. The outsole area is quite similar, once again, the the Hoka Stinson EVO. Presented below is a comparison of outsole widths with the Hoka Stinson EVO and some Salomon racing shoe products.
As can be seen the Sense Propulse is a slightly slimmed down Stinson, but is much wider in the heel than other Salomon comparison shoes. It should be noted that just 2 mm difference in width between shoes is very noticeable. Here we see much smaller differences in the forefoot width maximum on very different shoes but very large differences (up to 22 mm) in the heel width maximum. This indicates that the very wide heel element is critical to stability and comfort with the highly cushioned shoes. This makes sense from the reality of significant lateral motion vectors facilitated by the high cushion. With high cushioning and a narrow heel one might truly “tip over” whereas the wider heel will provide stability and a higher level of comfort.
As indicated earlier, I have put about 50 km of mostly trail running on the Propulse so far. This has been on dry trail with a mix of about 60% smooth single track, 40% technical single track, and numerous water crossings.
The feel of the shoe is very much like the Hoka Clifton from a cushioning perspective but has a much improved foot engagement that leads to enhanced trail feel, a sense of better stability, and increased confidence out of the box. This, I think, is due to the EndoFit system incorporated into the Propulse. Having a secure, slipper-like upper structure that integrates fluidly to the midsole and outsole just totally changes the running experience for the better when compared to other highly cushioned offerings. These are very comfortable shoes that will suit long, L1-L2 effort runs where either roads or trail are likely to adversely affect your feet.
The Propulse rides much better than the Hoka Stinson EVO primarily from the excellent proprioception, but there is also much less of a “dash pot” feel with each stride- something that has always been disconcerting with the other highly cushioned shoes that I have tried (with the exception of the Hoka Clifton). However, the increased weight of the Propulse (when compared to the Clifton or other racing shoes) is quite noticeable and detracts from an otherwise very pleasant experience. This is particularly significant for lighter runners where weight plays an increasingly important role.
Grip has been sufficient for dry trail conditions although I have not had these shoes on a complete spectrum of technical trail. Wet grip has been good as expected from the very large area, flattish outsole and, as mentioned earlier, the shoes drain and dry well.
I can recommend the Salomon Sense Propulse as a highly cushioned shoe with very good trail feel and high comfort. But this stability, trail feel, and comfort comes at the price of increased weight when compared to other similar highly cushioned shoes. Perhaps Salomon will bring a lower weight S Lab version out- not likely given the current ethos for S Lab products.
I’ll be putting more miles on these shoes in the near future but in the meantime they will be used for some long runs with significantly long downhill sections and also included in late race drop bags as potential replacement for the X-Series should my feet get beat up. Stay tuned.
$150 US. Pricey, considering the weight but Salomon are offering a highly cushioned shoe with good proprioception and a secure platform, something that is typically not evident in the current highly cushioned product offerings.
Salomon fit with Hoka Clifton cushioning at Stinson weight. Life is compromise!
* I have put reasonable mileage on the Hoka Stinson Evo, Huaka, Challenger ATR, and Clifton and the Altra Olympus. While I still put a pair of these maximalist shoes in my drop bag at later aid stations in longer races with significant late-race downhills, I have only twice used them in a race situation. The lack of proprioception with these shoes late in a long race is a bit alarming and possibly dangerous, at least for me.