Beta-hydroxy beta-methylbutyrate (HMB)

HMB is sold as a «muscle gain» product on the muscle proteolysis inhibition hypothesis. ISSN 2013 position stand recommended HMB 3 g/day for beginning resistance trainees and the elderly; in trained athletes hypertrophy effect is minimal. Sanchez-Martinez 2018 (Clin Nutr) systematic review showed no significant HMB effect on lean body mass in trained athletes. IOC consensus statement 2018 classified HMB as «evidence inconclusive» with potential benefit in resistance training beginners and sarcopenia in the elderly. For muscle gain IOC 2018 lists creatine monohydrate (3-5 g/day), adequate protein (1.6-2.2 g/kg), progressive overload and caloric surplus first-line; HMB is an additional option, not a substitute.

HMB is sold as a «post-workout recovery» product on the muscle damage inhibition hypothesis. ISSN 2013 position stand notes moderate reductions in muscle damage markers (CK, LDH) with HMB 3 g/day in resistance training beginners and extreme exercise (marathon, ultra-endurance); in trained athletes the effect is minimal. IOC consensus statement 2018 classified HMB as «evidence inconclusive». For recovery IOC 2018 lists adequate protein and calories, hydration, 7-9 hours of sleep; HMB is an additional option.