Behind the Scenes at adidas: Threshold Testing and Trail Shoe Prototypes

Last month, I had the chance to visit adidas HQ in Germany—a trip that brought together science, innovation, and some serious time with the latest TERREX trail shoe prototypes. For someone who’s always been curious about the tech behind what we put on our feet, it was a rare chance to not only learn but to help shape the gear that will end up on the trails with us.

Threshold Testing: Beyond the Numbers 

The visit kicked off with threshold testing. If you’ve been following my articles, you know I’m big on training by feel and balancing data with intuition. But this time, it was all about the numbers. These tests went beyond performance metrics; they were a deep dive into how my body reacts under different levels of effort. Adidas has a world-class lab, and the testing setup was really impressive.

The tests aimed to pinpoint my exact aerobic and anaerobic thresholds, mapping out at what Heart Rate my lactate levels reached these certain levels. What was surprising was just how precise the data was and how closely it aligned with my perceived effort. For instance that burning in your legs really indicates anaerobic threshold, something that is unsustainable to continue for long periods. The test becomes increasingly difficult as the treadmill increases in gradient over three minute reps… Until exhaustion. It’s worth it though. These insights will shape my training going forward and have given me a stronger trust in my heart rate monitor readings. I know the effort is there and the HR feedback can confirm this. The video below is a slightly creepy representation of me as a 3D model during testing.

Prototype Testing

Once the tests wrapped, it was time to shift gears and check out adidas’ latest TERREX trail shoe prototypes. This is where science met the trail, and I got to see first-hand how these shoes handle in a variety of conditions. I ran on treadmills and trails, testing for performance, grip, and comfort. The threshold numbers found earlier on, were not just for my own use, but they were also used to find a subthreshold range for the next round of prototype tests. This involved a sub threshold effort in a control shoe (current Agravic Speed Ultra), providing feedback, and then conducting the same test with different prototype samples.

For me, a good trail shoe goes beyond just cushioning or weight—it’s about how the shoe handles on technical terrain, grips in wet conditions, and adapts through long climbs, descents, and flat stretches. The new Terrex prototypes are driven by real feedback from athletes and trail runners alike. Without giving too much away, the innovations in these models are seriously promising and will add even more strength to an already stellar line-up of trail shoes.

What made this trip special wasn’t just testing shoes; it was the collaboration. I wasn’t there to simply test and nod—I was there to give candid feedback. That’s essential because we all have unique needs based on experience and preferences. Being part of this process means that when these shoes hit the shelves, they’ve been refined by people who are out there, pushing them to the limit. Ultrarunning gear demands durability and functionality that goes far beyond what most casual runners need, and it’s clear adidas understands that.

Looking Forward

Visiting adidas inspires me seeing the effort that goes into bringing an amazing product to market. It’s also exciting to see the direction TERREX is heading. As someone who spends a huge amount of time on trails. I’m looking forward to seeing these prototypes evolve through the next stages of testing and, eventually, making their way into real-world use. It’ll be great to see these shoes hit the trails, giving more runners the tools to enjoy their time outdoors to the fullest.

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