Effects of Hydrogen-Rich Water Supplementation on Exercise Performance, Autonomic Nervous System Recovery, and Blood Lactate Concentration During Repeated Sprint Exercise in Male University Athletes.
Chen Z, Chi M, et al. • Journal of sports science & medicine • 2026
Acute pre-exercise hydrogen-rich water ingestion attenuates the decline in power output, accelerates autonomic nervous system recovery, and enhances lactate clearance following repeated sprint exercise in male university athletes.
Key Findings
Results
HRW supplementation resulted in significantly higher average power output compared to placebo during repeated sprint exercise.
Study used a randomized, single-blind, placebo-controlled crossover design with 13 male university athletes (mean age 23.9 ± 2.0 years)
Exercise protocol consisted of 7 × 6-second all-out cycling sprints interspersed with 30-second recovery intervals
Effect size for average power output difference was d = 0.61, characterized as a medium effect
A one-week washout period separated the two experimental sessions
Results
HRW supplementation significantly reduced total work decrement and fatigue index during repeated sprint exercise compared to placebo.
Total work decrement was significantly lower in the HRW trial with an effect size of d = 0.62
Fatigue index was significantly lower in the HRW trial with an effect size of d = 0.64
Both effect sizes fall in the medium range, suggesting practically meaningful reductions in fatigue-related performance decline
These outcomes reflect attenuation of power output decline across the sprint series
Results
Post-exercise heart rate variability recovery was significantly accelerated in the HRW trial across multiple HRV indices.
RMSSD recovery was significantly faster in HRW versus placebo (d = 0.62)
LF/HF ratio recovery was significantly faster in HRW versus placebo (d = 0.82)
Sample entropy (SampEn) recovery was significantly faster in HRW versus placebo (d = 0.79)
DFA α1 recovery was significantly faster in HRW versus placebo (d = 0.79)
HRV was assessed at baseline, during exercise, and at 0–5 min and 10 min post-exercise
Results
Blood lactate concentration at 3 minutes post-exercise was approximately 1 mmol/L lower in the HRW trial compared to placebo.
The difference in blood lactate at 3 min post-exercise had an effect size of d = 0.64
Blood lactate was assessed at baseline, during exercise, and during post-exercise recovery
This finding suggests enhanced lactate clearance following HRW ingestion
The approximately 1 mmol/L reduction represents a medium-sized effect on post-exercise lactate accumulation
Methods
The study employed critical flicker fusion frequency as a measure of central nervous system fatigue alongside autonomic and metabolic measures.
Critical flicker fusion frequency was assessed at baseline, during exercise, and post-exercise
This measure was used alongside heart rate, HRV, and blood lactate to provide a comprehensive fatigue profile
The multi-modal assessment approach captured both peripheral and central aspects of fatigue and recovery
13 male university athletes participated, limiting generalizability to other populations
What This Means
This research suggests that drinking hydrogen-rich water (water infused with molecular hydrogen gas) before a series of intense cycling sprints can meaningfully benefit athletic performance and recovery. In a small study of 13 male university athletes, those who consumed hydrogen-rich water before completing seven 6-second all-out sprints with short rest periods between them maintained higher average power output and showed less fatigue across the sprint series compared to when they drank regular placebo water. The differences were moderate in size but statistically significant.
Beyond performance during exercise, the study also found that hydrogen-rich water appeared to speed up recovery of the autonomic nervous system — the system that regulates heart rate and other automatic body functions — in the minutes after exercise ended. Multiple measures of heart rate variability, which reflect how well the nervous system is recovering from stress, returned toward normal levels more quickly after the hydrogen-rich water trial. Additionally, blood lactate — a marker often associated with exercise-induced fatigue — was about 1 mmol/L lower three minutes after exercise in the hydrogen-rich water condition.
This research suggests that acute ingestion of hydrogen-rich water before high-intensity repeated sprint exercise may offer benefits for both performance and recovery, possibly by reducing oxidative stress or influencing metabolic processes, though the exact mechanisms were not directly measured in this study. Because the sample was small (13 male athletes only) and the study was single-blind, these findings should be considered preliminary, and further research with larger and more diverse populations is needed to confirm and extend these results.
Check Your Own Numbers
Upload your bloodwork. We'll cross-reference your results against this study and 4,700 others.
Chen Z, Chi M, Liu R, Ma L, Shen Y. (2026). Effects of Hydrogen-Rich Water Supplementation on Exercise Performance, Autonomic Nervous System Recovery, and Blood Lactate Concentration During Repeated Sprint Exercise in Male University Athletes.. Journal of sports science & medicine. https://doi.org/10.52082/jssm.2026.744