Hydrogen-rich water supplementation exhibits dose- and age-dependent effects on delayed-onset muscle soreness in professional soccer players

Abstract

Problem Statement: Effective inter-match recovery plays a crucial role in preserving performance and preventing injuries in well-trained soccer players. In this context, molecular hydrogen has attracted increasing attention in sports science due to its selective antioxidative, anti-inflammatory, and cell-signaling properties that may facilitate recovery. Among the various administration methods, hydrogen-rich water (HRW) appears to be the most common and practical form of supplementation. Nevertheless, the optimal dosage remains unclear, as recent evidence suggests that both the timing and amount of molecular hydrogen intake may influence recovery outcomes. Furthermore, its effectiveness appears to be modulated by individual characteristics such as age, highlighting the need for further targeted research. Approach: Professional soccer players were randomly assigned into two groups. Group 1 (n = 20, age 24.8 ± 4.3 years) received two 420-ml packs of hydrogen-rich water (HRW) or placebo, one prior to and one during halftime of a large-sided game. Group 2 (n = 18, age 25.4 ± 5.1 years) received two additional packs after the game. Each group participated in two games, with HRW and placebo administration randomized across games. Delayed-onset muscle soreness (DOMS) was assessed 24 hours post-game using a 100-mm horizontal visual analogue scale. The effect of HRW administration on DOMS was assessed in a dose- and age-dependent manner. Results: In younger players (<25 years), both two packs (placebo: 58 ± 5 mm, HRW: 42 ± 10 mm, p = 0.004) and four packs (placebo: 58 ± 11 mm, HRW: 41 ± 7 mm, p = 0.004) of HRW resulted in similarly significant reductions in DOMS. In contrast, among older players (≥25 years), two packs of HRW did not significantly reduce DOMS (placebo: 60 ± 15 mm, HRW: 54 ± 20 mm, p = 0.19), whereas four packs produced a significant reduction (placebo: 64 ± 10 mm, HRW: 42 ± 9 mm, p = 0.004). Conclusions: These findings suggest that a higher dose of HRW may be necessary to effectively reduce DOMS in older compared with younger soccer players. Therefore, both dosage and player age should be considered when implementing HRW as a novel recovery strategy in professional soccer to optimize its benefits for reducing muscle soreness and enhancing post-game recovery. Moreover, incorporating higher HRW doses in older players could represent a valuable addition to existing recovery protocols, as advancing age is associated with diminished antioxidant capacity, slower resolution of inflammation, and prolonged recovery.