Will Renwick hits the dirt to test out Merrell’s latest Tough Mudder trail shoe

Merrell has once again teamed up with Tough Mudder to release a shoe designed specifically to meet the demands of an obstacle race. Last year it was the All Out Crush Tough Mudder, this year it’s the Avalaunch Tough Mudder.

I haven’t actually tested these new trail shoes specifically on a Tough Mudder course yet but I did wear them for something fairly similar, both in conditions and wackiness: the Man v Horse in Mid Wales. It was wet, it was muddy, it was steep uphill and steep downhill and it was long (23 miles).


The Avalaunch served me very, very well. First of all, the grip is excellent. I didn’t slip in them at all, and that’s somewhat of a miracle given the conditions. The purchase they give is all thanks to the lugs which are 5mm in depth and multi-directional, laid out in a varied mix of triangles and horizontal and vertical strips. I didn’t have trouble with my feet sliding around inside the shoes either as the design of the uppers creates a very wrapping fit over the instep and at the ankle where the walls have a reasonable stiffness to hold the heel in place.


There’s absolutely no point trying to stop water getting into your shoes on a Tough Mudder, instead the priority should be making sure that water can get out. This is where the mesh panels on the uppers of the Avalaunch come in handy as they drain very well – and without letting in any debris. The lycra ankle cuffs did a decent job of keeping out debris as well.

The lacing system is the main difference between this Tough Mudder shoe and the last one, with the traditional lacing swapped for ‘speed-lacing’ which is basically a thin cord-like lace and toggled drawcord. This is easy to tighten and easy to undo, and it holds very well. I didn’t ever feel like I needed to tighten the shoes up while on the go. The only problem I had was that I found the excess lace kept popping out from the little Velcro sealed pocket at the top of the shoe’s tongue and this got a little irritating when I was running at pace. Perhaps there’s a knack to keeping it in place though.

RELATED: WIN a pair of Merrell Avalaunch trail shoes PLUS entry to a Tough Mudder


There isn’t much cushioning under foot, as was the case with last year’s Merrell Tough Mudder shoe, there’s just a slightly soft neoprene lining under the heel and that’s it. Also, the drop from heel to toe is just 7.5mm which most would class as minimal so there’s quite a bit of responsiveness underfoot and an ability to sense the ground. Whether this is a good thing or a bad thing depends on  individual preference.

This thin and simple midsole is a big factor in the low overall weight of the Avalaunch, with a pair weighing just 400g.


As shoes specifically for obstacle racing, these get a thumbs up from me. But what about for standard trail running? The grip and drainage are definitely up to scratch but you’ll need to be comfortable with a minimalist sole that sacrifices cushioning for responsiveness.

Price: £110