Can molecular hydrogen supplementation enhance physical performance in healthy adults? A systematic review and meta-analysis.

Abstract

A systematic review and meta-analysis incorporating 27 studies and 597 healthy adult participants examined how H₂ supplementation influences multiple dimensions of physical performance. Effect size analyses revealed no statistically significant improvements in aerobic endurance (VO₂: SMD = 0.09), anaerobic endurance (SMD = 0.19), or muscular strength (SMD = 0.19). However, lower limb explosive power showed a small but significant improvement (SMD = 0.30, p = 0.018). H₂ supplementation was also associated with significant reductions in rating of perceived exertion (SMD = −0.37, p = 0.009) and blood lactate concentration (SMD = −0.37, p = 0.001), while average heart rate was unaffected. Evidence quality was assessed using the GRADE framework. The authors conclude that H₂ may benefit explosive power and fatigue-related markers but does not appear to meaningfully enhance endurance or strength outcomes, and that more rigorously designed trials are warranted.

Mechanism

H₂ is proposed to reduce exercise-induced oxidative stress and inflammatory responses through its antioxidant and anti-inflammatory properties, thereby attenuating blood lactate accumulation and perceived exertion during physical activity.