Pre-Exercise Ingestion of Hydrogen-Rich Cold Water Enhances Endurance Performance and Lactate Response in Heat
This 2025 randomized, double-blind crossover study examined whether drinking hydrogen-rich cold water (HRCW) before exercise could improve endurance performance and reduce heat stress during exercise in hot conditions. Twenty-two trained male sports science students completed shuttle run tests in 32 °C heat under three conditions:
- hydrogen-rich cold water (HRCW),
- cold water alone,
- and cold water combined with external cooling.
Researchers found that pre-exercise ingestion of 500 mL of hydrogen-rich cold water significantly improved endurance performance compared to cold water alone. Participants consuming HRCW showed:
- a 4.8% increase in maximal aerobic speed (MAS),
- more than 20% more shuttle run repetitions,
- lower blood lactate levels,
- reduced dehydration,
- lower perceived exertion,
- improved mood scores,
- and reduced post-exercise body temperature.
Interestingly, the combination of external cooling and cold water lowered body temperature but did not improve performance as effectively as hydrogen-rich cold water alone. Researchers suggest that molecular hydrogen may provide benefits beyond simple cooling by helping reduce oxidative stress and support mitochondrial energy production during exercise in the heat.
The paper discusses several possible mechanisms by which molecular hydrogen may improve endurance performance, including:
- selective reduction of harmful reactive oxygen species,
- improved mitochondrial ATP production,
- enhanced antioxidant defenses,
- improved metabolic efficiency,
- and reduced neuromuscular fatigue.
Researchers also observed significantly lower blood lactate concentrations after exercise in the HRCW condition, suggesting improved metabolic coordination and reduced exercise stress during heat exposure.
In everyday language, this study suggests that drinking hydrogen-rich cold water before exercise in hot conditions may help athletes maintain endurance, reduce heat stress, improve comfort, and recover more efficiently during intense activity.
The authors conclude that hydrogen-rich cold water may serve as an effective pre-cooling and performance-support strategy for exercise in hot environments.
Download this article from Medicina (Khlifi et al 2025):
Mechanism by Which Hydrogen-Rich Water Mitigates Exercise-Induced Fatigue
This 2026 study published in Medical Gas Research explored how hydrogen-rich water (HRW) reduces exercise fatigue at the molecular level. Researchers used a forced-swimming mouse model combined with metabolomics, oxidative stress testing, muscle tissue analysis, and cellular experiments to investigate the biological pathways involved. The study found that hydrogen-rich water significantly improved exercise endurance and recovery in fatigued mice. HRW:
- increased treadmill running distance,
- improved rotarod performance,
- reduced blood lactate,
- lowered blood urea nitrogen (BUN),
- reduced creatine kinase (CK),
- preserved muscle glycogen,
- and reduced visible muscle fiber damage.
One of the most important findings was the identification of a specific anti-fatigue signaling pathway activated by HRW:
IRG1 → Itaconate → Nrf2 → HO-1
The researchers discovered that hydrogen-rich water increased expression of:
- IRG1 (Immunoresponsive Gene 1),
which increased production of: - Itaconate, a natural metabolic signaling molecule,
which then activated: - Nrf2, the body’s master antioxidant response regulator,
leading to increased: - HO-1 (Heme Oxygenase-1),
a protective antioxidant and anti-inflammatory enzyme.
The paper concludes that this pathway helps reduce oxidative stress caused by strenuous exercise and improves recovery from fatigue. The graphical abstract on page 1 visually summarizes this cascade and its role in reducing oxidative stress in muscle tissue.
The study also showed:
- lower oxidative stress markers (malondialdehyde),
- increased antioxidant enzyme activity (SOD and glutathione peroxidase),
- improved mitochondrial function,
- and reduced reactive oxygen species (ROS) in muscle cells treated with HRW.
Importantly, the authors suggest that hydrogen-rich water does not merely “neutralize free radicals” directly. Instead, it appears to activate the body’s own endogenous antioxidant defense systems through metabolic signaling pathways. That distinction is scientifically important because it may explain why molecular hydrogen shows broad protective effects across multiple physiological systems.
In everyday language, this paper suggests that hydrogen-rich water may help the body:
- recover faster from physical stress,
- preserve muscle energy,
- reduce oxidative damage,
- support mitochondrial performance,
- and activate natural cellular recovery pathways during intense exercise or fatigue states.
The authors conclude that hydrogen-rich water may represent a practical, low-toxicity strategy for improving exercise recovery and reducing fatigue-related oxidative stress.
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Effects of Hydrogen-Rich Water on Prolonged Intermittent Exercise
This 2018 study investigated whether drinking hydrogen-rich water (HRW) could improve performance and reduce fatigue during repeated high-intensity intermittent exercise similar to many team sports. Researchers tested trained soccer players performing repeated sprint and endurance activities after consuming hydrogen-rich water for 7 days.
The study found that hydrogen-rich water significantly reduced declines in peak power during repeated exercise sessions. Athletes consuming HRW maintained better performance output and showed signs of reduced muscular fatigue compared to placebo.
Researchers observed:
- improved repeated sprint performance,
- reduced fatigue accumulation,
- preservation of peak power output,
- and lower physiological stress during prolonged intermittent exercise.
The paper discusses how molecular hydrogen may help by:
- reducing oxidative stress generated during intense exercise,
- improving mitochondrial efficiency,
- lowering muscle fatigue,
- and helping the body maintain energy production during repeated exertion.
Importantly, the authors noted that the benefits appeared most pronounced during prolonged, repeated bursts of exercise rather than short single efforts. This aligns well with sports involving repeated sprinting, rapid recovery demands, and sustained high workloads such as soccer, basketball, football, hockey, and combat sports.
In everyday language, this study suggests that hydrogen-rich water may help athletes maintain performance longer during demanding workouts or sports where fatigue normally builds over time.
The findings support growing research that molecular hydrogen may improve exercise tolerance and recovery by reducing oxidative damage and helping muscles function more efficiently under stress.
Effect of Molecular Hydrogen Application on Recovery After Endurance Running in Untrained Men
This 2025 randomized, double-blind, placebo-controlled crossover study examined whether hydrogen-rich water (HRW) could improve recovery after a 5 km endurance run in untrained men aged 20–30 years. Sixteen participants completed two separate 5 km runs spaced 7 days apart while consuming either HRW or placebo water. Participants consumed a total of 3780 mL of HRW, including a prophylactic dose before exercise and an additional dose after the running protocol. Researchers evaluated post-exercise muscle soreness using a Visual Analog Scale (VAS) and measured explosive lower-body power using countermovement jump (CMJ) testing.
The study found that HRW significantly reduced delayed onset muscle soreness (DOMS) at:
- 1 hour post-exercise (p = 0.005)
- 4 hours post-exercise (p = 0.002)
- 24 hours post-exercise (p = 0.016)
Although HRW reduced muscle soreness, researchers did not observe statistically significant improvements in explosive lower-body power measured by vertical jump performance. However, the data suggested a relationship between reduced soreness and improved recovery dynamics after exercise. The paper also reviews earlier human studies showing that molecular hydrogen may help reduce exercise-induced oxidative stress, fatigue, and muscle soreness following endurance and high-intensity exercise.
In everyday language, the research suggests that hydrogen-rich water may help reduce post-exercise muscle soreness and improve recovery comfort after endurance exercise, particularly in individuals who are not endurance-trained.
The authors conclude that HRW may represent a useful recovery strategy for reducing exercise-induced muscle soreness in recreational or untrained individuals following endurance running.
Download this article from Palacký University Olomouc (Pospíšil 2025):