PRIME ABS was created by former gymnast Andy Speer — a Men’s Health Top Trainer, a Reebok athlete, and one of the world’s most sought after fitness experts.

Speer is one of the lightest men ever to complete the Russian Kettlebell Challenge, in which he had to perform a pistol squat, a single-arm press, and a pullup, each with a 48-kilogram (106-pound) kettlebell. Speer credits his success in the weight room to his years of gymnastics training, which he’s incorporated into PRIME ABS.

Follow along with Speer to push your limits and achieve legendary leanness.