Salomon S-Lab Sense Ultra

S-LAB SENSE ULTRA: MIDSOLE

Cushion: Firm

Sole Flexibility: High

Rock Guard: Yes, Forefoot and Midfoot

The midsole of the Ultra is very firm in the forefoot and mid-foot, and slightly softer in the heel.

There is a flexible rockplate that extends from the forefoot through the midfoot that gives a nice blend of feel of the trail without punishment.

Salomon S-Lab Sense Ultra vs. New Balance MT110

Compared to the similar thickness, similar firmness, and similar weight of the New Balance MT110 shoe, however, the Sense Ultra’s refinement really shines through.

On technical, rocky terrain, the MT110 can be punishing, especially in the mid-foot, where the MT110 has no outsole or rock plate. (The MT110 does have a rockplate or “rock stop” protection, but it is in the forefoot only.) The Sense Ultra is as flexible, if not slightly more flexible than the MT110, but manages to combine incredible trail feel with excellent rock protection. Compared to the Sense Ultra, the MT110 felt very hard and unforgiving.

Salomon S-Lab Sense Ultra vs. Brooks Pure Grit

The Brooks Pure Grit offers a similar level of protection from sharp objects as the Sense Ultra, but in a thicker, softer, heavier midsole, which feels less responsive and provides less trail feel than the Ultra (though not compared to many other shoes).

I’d say the Pure Grit gives up about 50% of the feedback of the trail into your foot, so if you are running long distances on loose, rocky, uneven terrain, the Sense Ultra may eventually make your feet a bit more sore—or at least until you further strengthen and build up your feet. (On very rough terrain, I currently can’t go more than 10-15 miles in the Sense Ultra, while 20+ miles in the Pure Grit is no problem.)

As always with gear, it really depends on what you are after:

On fast, smooth singletrack and slower, technical terrain, I would take the Sense Ultra over the Pure Grit 100% of the time.

But on long, blown out, fire road descents that allow you to bomb down with a full stride, but that are littered with apple-sized rocks everywhere, I would at least think pretty hard about how long the trail is in total, and therefore which shoe makes more sense, as the Pure Grit is a little less taxing, but also provides a little less responsiveness and speed.

Salomon S-Lab Sense Ultra’s OS Tendon

The midsole of the Sense Ultra embeds a dense material called the OS Tendon that links the heel to the toe, and this material is said to provide additional rebound as the shoe returns from being stretched.

While I can’t say for sure whether this is the case, I can say that the Sense Ultra is probably the most responsive shoe in terms of transitioning from compression to propulsion I have ever run in. The shoe feels like it has a natural acceleration that helped me keep turning my legs over and moving forward. For me, this was most apparent on flatter, technical trails. The shoe helped me hold my speed and spring forward over and around roots and rocks.

The midsole uses a thin TPU film layered between the two layers of EVA. This “ProFeel” film serves as the rock protection, and is exposed where the sole is cut away to increase flexibility. I was initially concerned about getting jammed with rocks directly through the shield, but that has not proven to be the case in the least. I have yet to receive a single painful rock strike, which I seemingly experienced every time out in the MT110.

Forefoot and Midfoot Striking

Because of the midsole design of the Sense Ultra, I found that cushioning was equally well suited for either forefoot or midfoot strikes. (Again, if you’re not already a forefoot or midfoot striker, these shoes will require you to adopt this kind of style to be comfortable.)

I personally appreciate this versatility, as I like to change up my stride and strikes on long descents to minimize fatigue by changing up the muscle groups at work. I find this to be a good way to get a little refresh while still moving fast.

S-LAB SENSE ULTRA: OUTSOLE

• Grip (dry): Exceptional

• Grip (moist): Exceptional

• Grip (muddy): Not Tested

• Durability: Good to Very Good

Durability

Salomon has used Contagrip outsoles on its running shoes for a number of years, and the wear-rate of this rubber has proven to be excellent.

The outsole has lasted far better than the ones on either my New Balance MT110 or my Brooks Pure Grit. With 175 miles on the shoes thus far, the outsole and midsole are finally starting to get a little tired, and the cushioning is starting to get thin. I figure I’ll get another 25-50 miles out of them, then they will be retired.  I feel that mileage is okay for a ‘race-day-style’ shoe in the Sense Ultra’s weight class, especially when considering that I am 200 lbs., and am running primarily on exposed rock and decomposed granite.

(For reference, I get 200 miles, max, out of the New Balance MT110 before they become a slippery, uncushioned mess, but I can get 250-300 miles out of the Brooks Pure Grit, and generally retire those because the upper is too streched out, not because the outsole and midsole are toast.)

Lugs

The lug design on the Sense Ultra is top notch. To me, these shoes set the benchmark for the combination of speed and traction in dry conditions. The Sense Ultra never slips on kitty litter, exposed granite slab, wet river rock, or on wet roots.

I don’t run in the rain here in Utah (it is the desert, after all), so I can’t comment on mud performance. But in normal dry, alpine conditions, I have found them to offer the perfect combination of traction and speed.

S-LAB SENSE ULTRA: UPPER

The upper of the Sense Ultra is, as far as I can tell, the same as that of the original Salomon S-Lab Sense. It features a seamless construction consisting of plasticy/rubbery frame that is laminated to a breathable, mesh material on the sides and the top of the toe box.

Salomon has built in a nice extra-thick rubber toe cap, which really works well to protect the toes. (The Sense Ultra’s toe box offers substantially more protection than the Pure Grit’s.)

The plastic/rubber structure of the upper, combined with the Sense Ultra’s narrower toe box, has done a remarkable job of keeping my foot planted in the shoe and preventing lateral foot-slide.

A very common run for me has a technical ~1.5 mile out-and-back section that sidehills around the mountain. The trail is not bench cut or particularly well defined, so the trail falls away, and your downhill foot is constantly fighting to stay on trail. With the Pure Grit, the shoe would often stretch with these lateral fall-away loads, and my feet would slide.

The New Balance MT110 has been my benchmark for preventing foot-slide, as it has a rigid plastic upper than keeps your foot locked in at all times. The Brooks Pure Grit is much more compliant, and with each step, I can feel strain on my ankles as my foot slides downhill and struggles to keep traction due to the flex of the upper.

I’ve found the Salomon S-Lab Sense Ultra to be every bit as good as the MT110 here. My foot is held in place relative to the sole, without any sliding or slipping. The materials used in the frame of the Sense Ultra are somewhat similar to the MT110‘s upper, so this is not a surprise.

The seamless construction of the Salomon, however, is a notch better than the MT110, which has a seamless internal sock, but two big seams on the medial instep that can and do wear out with time.