Background
Hydrogen gas has been posited to alleviate fatigue and mitigate declines in exercise performance through the reduction of oxidative stress induced by high-intensity exercise. However, the diversity of blood markers employed to evaluate hydrogen gas's antioxidant capabilities limits a comprehensive understanding of its mechanistic effects. This study evaluated the impact of hydrogen-rich gas (HRG) on metabolites following sprint interval exercise using metabolomics approaches, aiming to elucidate its underlying mechanisms of action. Results: Compared with placebo (air), HRG inhalation significantly improved mean power, fatigue index and time to peak for the fourth sprint and significantly reduced the attenuation values of peak power, mean power and time to peak between the first and fourth. Metabolomic analysis highlighted significant upregulation of Acetylcarnitine, Propionyl-L-carnitine, Hypoxanthine, and Xanthine upon HRG inhalation, with enrichment pathway analysis suggesting that HRG may foster fat mobilization by enhancing coenzyme A synthesis, promoting glycerophospholipid metabolism, and suppressing insulin levels. Conclusion: Inhaling HRG before sprint-interval test enhances end-stage anaerobic sprint capabilities and mitigates fatigue. Metabolomics analysis suggests HRG potentially accelerates fat oxidation during rest periods and facilitates greater ATP replenishment for later sprints, by mitigating mitochondrial oxidative damage, enhancing aerobic efficiency, and stimulating fat mobilization.