Despite an extensive pedigree in athletics, Adidas has traditionally kept a somewhat low profile in the trail and ultrarunning space, even with a string of solid offerings in their lineup. That profile should increase this summer with the release of the Terrex Speed Ultra, the result of two years of development and testing by Adidas athlete Tom Evans during the Ultra-Trail World Tour. This model fills a gap for an all-out performance trail racing shoe, with enough versatility and durability to withstand high-mileage efforts. The Speed Ultra will also be the primary shoe for Timothy Olson’s current Pacific Crest Trail FKT attempt. The goal was to balance lightweight design with Adidas’s well-established performance technologies such as the Boost midsole and Continental rubber outsoles to meet the demands of ultra-distance racing.
The upper is constructed of a thin but durable mesh that wraps around the entirety of the shoe. This mesh has a few overlay points at the toe and heel areas, as well as the sides where the signature Adidas striping is located. The mesh upper is surprisingly durable and besides becoming slightly dirty, had no visible signs of wear after well over 100 miles of testing on the trail. The upper features many points of thin mesh interspaced with more cushioned areas which both reduce weight and allow for a more breathable shoe.
The tongue of the Speed Ultra is thinly cushioned but provides a snug fit, and is interspersed with holes to provide more breathability. Depending on the personal lacing of the shoe, the Speed Ultra can be slightly tricky to take on and off. Some of our testers prefer a heel-lock style lacing pattern and did notice that the opening needs to be worked and loosened a bit before sliding a foot down into the shoe. This extra effort becomes more of a pro than a con when the shoes are on, as they feel very snug and secure on the foot. That being said, we did find that the shoes run true to size.
As with most high-tech performance shoes, the focus of the Speed Ultra is in the midsole, which uses a combination of the famous Boost TPU compound and a lighter weight LightStrike EVA layered on top. Both materials deliver responsive and highly cushioned rides; where they differentiate is that the Lightstrike is much lighter and provides increased cushioning for minimal added weight, while the Boost has high energy return along with stronger durability and resilience. The Boost material is also more resistant to temperature changes and retains its properties and overall feel during longer events and throughout the full lifecycle of the shoe. We found this combination provided very comfortable cushioning and excellent energy return when compressed, with a lightweight overall feel that makes leg turnover feel easy. With a midsole platform that drops 8mm from heel to toe, the Speed Ultra will more easily favor heel strikers than midfoot landers.
Continental, a company who rose to prominence with their bike and car tires, has been partnering with Adidas to make their rubber outsoles for running shoes for the last 10 years. It’s a tried and true formula that works well on the Speed Ultra. Lugs are relatively shallow at 2.5mm, making them the equivalent of a gravel bike tire rather than a uber-knobby mountain bike ride, and are multi-directional to provide a strong grip on a variety of surfaces. During our testing we ran on dirt-packed roads, snowy mountaintops, steep crushed stone and loamy redwood trails with no traction issues at all.
Another established Adidas technology found on the Speed Ultra is the Torsion System positioned between the lugs of the forefoot and the rearfoot. This is a thermoplastic insert that allows flexibility through the midfoot while providing a more stable heel-to-toe strike. The system works as advertised to create a smooth transition from heel to toe, but one drawback we noticed is that with the absence of lugs, this section of the outsole gets easily caked with mud on wetter runs.
The Adidas Terrex Ultra Speed is a lightweight and race-ready shoe intended for a variety of trail conditions. Lightstrike midsole EVA and Boost TPU in the midsole provide smooth and efficient energy return while keeping the flexibility in the midfoot thanks to the Torsion System. Best suited for trail races, the Ultra Speed may not have the cushioning needed for mortal runners to push past the 50k or 50-mile distance.
Features and Specs:
- Weight (men’s / women’s): 8.5oz / 7.4oz
- Stack height: 27/19mm
- Heel-toe drop: 8mm
- Upper: breathable mesh with abrasion-resistant weldings
- Midsole: Boost TPU compound with Lightstrike EVA cushioning
- Outsole: Continental rubber with multidirectional 2.5mm lugs
- MSRP: $160