Anabolic Catalyst. Supports Increased Muscle Mass and Strength. X-Factor helps amplify muscle responsiveness to exercise, supporting faster and more profound increases in muscle size and strength. Independent clinical trials have demonstrated statistically strong improvements in bench press 1-rep max (44%), peak muscle power (600%), average muscle power (223%), and muscle endurance (250%) with 50 days of supplementation (Journal of the International Society of Sports Nutrition. (1)S1-S29, 2006). Developed and patented by performance-enhancement scientist William Llewellyn.