The Adidas Prime X3 Strung is a max-cushioned training shoe built for speedy efforts over long miles. Priced at $300, it sits in a category of its own as a double-plated, 50mm-stacked behemoth. The first version of the Prime X Strung was a beloved favorite—worthy of Supwell Hall of Fame status. It was one of the first shoes to defy World Athletics’ race shoe rules, designed to be the fastest marathon racing shoe without restrictions. It featured 50mm of stack in the heel, a carbon fiber plate, energy rods, and three layers of race foam. It was very fast but also narrow and unstable, especially for slower efforts or on uneven terrain. With version 2, Adidas made drastic changes—increasing the weight by 50 grams and adding a wider base for more stability. While it improved balance, it also completely changed the unique character and ride that made the OG so special. The Prime X3 Strung feels like a return to balance. It lands somewhere between the OG and v2—both in weight and stability (especially in the forefoot). It combines the soft, unstable heel of the OG with the responsive, snappy forefoot of the v2. It retains the same 50mm stack, three layers of Lightstrike Pro foam, a full-length carbon plate, and Adidas’ Energy Rods 2.0. At $300, it feels like a $300 shoe—especially if you're seeking a unique, high-tech running experience. It excels at fast paces and when you're putting down power. We logged 3 miles at marathon pace during our first run, and it felt responsive and exciting. That said, there are lighter shoes that offer more speed assistance without the added bulk. We could see it serving as a long run trainer, a marathon shoe for larger runners, or a Zone 3 cruiser for those who want a fun long run shoe. Still, the Prime X Strung OG remains the superior shoe in our opinion—its smooth, "disappearing-on-foot" feel made it a unicorn. If you’re looking for an exciting, bouncy, tech-packed ride, the Prime X3 Strung absolutely delivers. It’s a bold showcase of everything Adidas has to offer—and then some.
