When Adidas Terrex began designing the Agravic Speed Ultra over two years ago, the team had one goal: to build the fastest off-road shoe. Prototypes have been on the feet of Adidas Terrex runners topping podiums in the last few years, from Petter Engdahl in CCC to more recently Tom Evans’ win at the 2023 Western States 100. Now the Agravic Speed Ultra is finally available to the rest of us.
Pros
- Relatively firm midsole excels on smooth trails
- One of the fastest trail racing shoes
- Continental rubber is grippy on rocks
Cons
- Short lugs can slip in mud and on loose ground
- The plate can make it feel unstable on extremely technical trails
| Type | Trail Racing |
|---|---|
| Heel Stack | 42 mm |
| Forefoot Stack | 34 mm |
| Drop | 8 mm |
| Weight | 9.5 oz (M), 7.8 oz (W) |
| Lug Height | 2.5-3.5 mm |
The Agravic Speed Ultra uses a lot of the tech you’ll find in shoes like the Adidas Adios Pro 3 and Prime X, but Director of Innovation at Adidas Terrex, Jeff Morris, told Runner’s World this isn’t a copy/paste with a new outsole. “We were absolutely able to tap into some of those things for the Agravic Speed Ultra, but how those things were implemented was really centered around the trail running athlete.”
I was lucky enough to get my hands on a pair as I built up to running the Western States 100, and I was able to put more than 100 miles of training on the shoe. Like other modern trail racers we’re seeing, the Agravic Speed Ultra has a thick midsole—42mm under the heel and 34mm at the forefoot. That may sound like a recipe for disaster on uneven ground, but the midsole spreads quite a bit wider underneath the foot in order to keep your foot stable.
It’s also not the squishiest midsole out there. It’s made from Lightstrike Pro, which is a thermoplastic polyester elastomer (TPEE) that’s more durable than the PEBA used in many super shoes and needs a short break-in period. That also means it won’t pack out and flatten as much over the life of the shoe. I appreciate the stability and firmness when I encounter technical trails. It doesn’t have any extra rolling or compression that can sap confidence in foot placement when you need it most.
While I kept the Agravic Speed Ultra to mostly Western States–like trails, I did end exploring on one run that veered away from the smooth section of the Appalachian Trail I had been running. That took me onto some much more technical and rocky trail than I had planned for. There, the shoe felt quite tippy and unstable. That’s not unlike other plated shoes I have run in, so it’s important to remember that this shoe was designed around faster, more flowy trails. For technical terrain, a more flexible, nonplated shoe will suit most runners better.
Also for all-out speed, the outsole has much shorter lugs than you will find on most trail shoes. A mix of 2.5mm and 3.5mm lugs help shave weight, and make it roll more like a road racer. The tradeoff is that, in loose or wet conditions, the shoe won’t have much bite. The Continental rubber outsole, however, is fairly sticky and holds pretty well on rock faces.
The upper is very light and thin, similar to the speedier Adidas road shoes. It won’t provide much protection against rocks or roots, but it breathes well and doesn’t absorb water. The fit provides a good lockdown for running at race pace, and navigating winding trails, but it does run long, which led to my foot slipping a bit on steeper descents. So consider sizing down at least a half size.
While many of the top-end trail race shoes are starting to match road race prices of $250 or higher, the Agravic Speed Ultra comes in at a relatively reasonable $220.
