Written by Kurt Dusterhoff - http://cotswoldrunning.blogspot.co.uk
One of the simplest joys in running is having the opportunity to wear a new (clean!) pair of shoes. It's even better when you have no idea what they'll be like, and you find out they fit like a glove - which is what happened when I put on the pair of S-Lab Sense Ultra 4 SG shoes that Salomon sent me to test out (yes, they sent them free, and no, they haven't any input into this review). I hadn't been planning to hit the trails when I put them on, but quickly changed my mind and added a little hill repeat session to my evening itinerary.
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| First impression - aren't they pretty! And wow, the snug fit is impressive. |
Unfortunately, it had been a pretty dry week, so I wasn't sure how much soft ground I would be able to find on my chosen route. Still, I headed out to Broadway to find a little section of the Cotswold Way (and the Evesham Ultra route) that would give me a selection of terrain and gradient to play on.
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| A nice little boggy section helped test the Sense Ultra's water retention. |
On the way to the hill, I managed to find some boggy mud to traipse through. One of those little irritants that can ruin a good race is a shoe that holds onto water too well. Even after submerging in sloppy mud a few times, the Sense Ultra let the water go quite easily - no quibbles there, then!
That weekend, I took them out for a more daunting hilly run of around 3 hours - not long in ultra terms, but long enough to get a feel for the shoe over mud, grass, rocky path, a bit of road, and various dirt and gravel tracks. Over the next couple of weeks, I also managed to get them onto old quarry waste piles, wet and dry sandy beaches and some coastal trails, to give me a good idea of how they behaved on the wide variety of terrain that makes up most trail ultras in the UK.
The short review: a very good shoe, with a slightly narrow toe box, snug fit, and reasonable grip.
The long review? Carry on reading! As usual, if the picture is pretty, it's probably Nic's. If it's functional, it's mostly likely mine.
The Shoe
The Salomon S-Lab Sense Ultra 4 SG is a low-rise (4mm drop), light, sturdy shoe designed for long distances over soft/wet ground. My Size 9.5 (UK; US10, EU44) weighs in at ~270g (+/- a bit of mud), which is definitely on the lighter end of what I'd want to wear for 8+ hours.
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| Plenty of lugs, a really light mesh upper, and enough molding to give some lateral support and rock protection. |
I know a lot of people have stopped talking about heel drop, and a load more don't really care about the distance from their foot to the ground - if you're one of those people, you should probably just skip the rest of this paragraph. I trip a lot, and roll my ankles a lot, but I've found that I do less of both if my shoe isn't offering me much of a barrier to the ground. Unfortunately, I've also got a long history of foot and calf issues, which is best managed over long distances by a reasonably elevated heel relative to the toe. So, when I saw the 13mm heel (compared to 20mm on the Speedcross), I was really looking forward to taking them for a spin. The toe still has plenty of cushioning (9mm compared to 6mm in the Fellraiser, and 9mm on the Speedcross), which comes in handy when you plan to be out in them all day.
The Fit
In a word: glovelike. The Endofit (TM) upper, which basically acts like a sock, is fabulous. I'd be tempted to go sockless if I didn't want the extra protection from grit and grime that a sock gives.
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| The Endofit (TM) upper encases the foot by attaching at the insole. Soooo comfy! |
On my right foot, I did find that top of the lacing system crossed just at a particularly uncomfortable spot on the top of my foot, which would cause real problems on a long run. It's not an uncommon problem for me, due to the difference in length between my right and left foot, and it took a few runs to sort out. Basically, if I pull the Quicklace (TM) tight in an off-centre position, then I can nail the fit.
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| See how the right foot has the tab pulled off-centre. Little adjustments like that can make or break a run. |
On steep descents, I will admit that I was happy to have recently lost my big toenails. The snug fit was great, but it was even better to feel the front of my toe hitting the shoe without my toenail getting jammed. For many of you, toenails aren't a worry anymore. For the rest, let this be a good reminder to try before you buy to make sure you are happy with the sizing. If you want a bit more room to play with, I'd suggest the Fellraiser.
The Grip
The shoe is designed for grip, and it does an OK job. I had some nice long, muddy hills on one test run, and was with a friend who wore Speedcross. I faired alright, slipping a bit on some muddy ascents, but the soles did hold onto the mud a bit, so by the top I couldn't compete with him on grip.
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| Trapezoidal lugs offer a fair amount of grip on soft ground, but on muddy ascents, the Speedcross held better. |
After a few checks of the soles and some different types of mud (we have plenty of variety around here), I'd say that the shoe releases mud well across the ball of the foot, where the shoe flexes most, but not quite as well as I needed it to under the toes, where you need the most grip running up a muddy hill.
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| The cutouts and lug shape don't seem to allow sticky mud to release optimally from my hill session. |
For more "normal" soft ground running, the shoe gripped very well. Downhill, flat, wet beach, dry beach, all presented me with no difficulties. Like with most (all?!) shoes, wet limestone is pretty slippery, but where the rock offers some rough texture, the shoe grips well enough. On the loose quarry waste hills that make up a bit of the Cleevewold 14 trail race, I had absolutely no problems with control going down or with digging my toes in and climbing (slowly) up.
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| Soft ground, all right - and it all stayed on the beach. The outsole released wet sand very nicely. |
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| On muddy coastal trail, the grip was excellent and the mud-release faultless. |
Comfort
I've not taken the Sense Ultras out for more than 3 hours at a time yet, but my feet have come back from all of the test runs happy. I would say that, if you don't normally wear shoes with a lot of flexibility and not a lot of structure, that you should be very careful to gradually up your distance in these. After 3 hours of varied surfaces and lots of hills, my feet were a little tired. Equally, if you're coming from a higher-heeled shoe, take your time getting used to the lower sole.
On hard ground, unsurprisingly, the shoe feels a bit under-cushioned (remember, this is the SG variety we're talking about!). So, where there's a lot of road, sun-baked track, or hard rocky trails, you probably don't want to go with this soft-ground specialist. On the springy moors, grassy fields, beach, and muddy trails, I found the shoe quite a pleasant ride. Sharp rocks will let you know they're underfoot, but didn't leave any bumps or bruises on my feet.
Things I Like
Things I'd Like to See Improved
It's minor, but it really bugs me that the lace pocket is pretty useless - it's under the top laces when they're tightened. It offers nothing in its current form, so either lose it or put the opening at the top so it can actually do the job it's meant to do. I'd also like to see a chevron lug instead of the trapezoid blocks, at least at the front. It offers better grip, especially on contours, and seems to release the mud better. I would like to see the cost come down, since it's currently listed at 40% more than the very popular Speedcross: it's hard to decide to change shoe models with that big a price differential, but I'm hopeful that time and sales volume will help that to change. And finally, as with all Salomons I've worn, I seem to get a squeak in the lacing of the left shoe - it would be nice for that to disappear.
Summary
It's a good shoe, a very good shoe. After a few runs, I was dubious about wearing it for an ultra, because the snug fit doesn't give you much space to expand. But, now that I've had a chance to put some miles in, I can't see any reason to worry. I'd certainly be happy to go up to 40 miles in them in most conditions, and probably quite a while longer if it's properly wet/soft.