As of December 2015, the majority of online reviews at Amazon.com, Muscle & Strength and GNC say that Xtend bodybuilding supplements are effective. Reviews at Amazon.com indicate that Xtend Intra-Workout Catalyst increases endurance, aids muscle recovery and helps reduce muscle cramps by replacing lost electrolytes. Xtend Intra-Workout Catalyst averages ratings of more than four out of five stars at Amazon.com.
Xtend BCAAs has an overall rating of more than nine out of 10 at Muscle & Strength's website. Reviewers say that it dissolves well, tastes good and has no aftertaste. Some reviewers experience less delayed onset muscle soreness, increased energy levels and faster recovery after workouts. Many exercisers find they are able to work out longer and harder.
Xtend earns 4.5 out of five stars at GNC's website. One reviewer says that it helps sustain energy levels but does not cause sleeplessness like other supplements. Reviewers claim the product decreases both muscle fatigue and post-workout soreness. Some reviewers mention that it prevents cramping, boosts energy and speeds recovery. While some commentators use it just during workouts, others drink it throughout the day.
Xtend is made by Scivation, according to the company's website. The various Xtend products focus on different outcomes, including replacing electrolytes, increasing energy and supporting muscle growth.