Benefits of hydrogen-rich jelly during constant load testing in healthy adults: A pilot double-blind randomized crossover trial

PurposeExercise-induced fatigue hinders activity. Molecular hydrogen may enhance mitochondrial function and efficiency, but its effects in non-athletes are unclear. We evaluated whether hydrogen-rich jelly (HRJ) enhances high-intensity exercise in non-athletes. MethodsThis double-blind, randomized, placebo-controlled crossover trial (UMIN000053818) enrolled 50 healthy adults, who were randomly assigned in a 1:1 ratio to ingest HRJ first or placebo jelly (PJ) first. Participants consumed 10 g of HRJ or PJ on three occasions: 24 h, 90 min, and immediately before exercise. An incremental test determined anaerobic threshold (AT), followed by 30 min of cycling at 120% of AT. Oxygen consumption (VO{square}) and heart rate (HR) were continuously monitored; blood lactate was sampled every 5 min. Condition differences were assessed with paired t-tests and mixed-effects models. ResultsOf the 50 participants, 48 completed all measurements, and analyses were restricted to the 28 who completed the entire 30-min exercise session (13 women, 46.4%). The mean age was 41.7 {+/-} 11.5 years; mean BMI 22.3 {+/-} 2.6 kg/m{superscript 2}; and mean peak VO{square}, 26.8 {+/-} 5.9 mL/kg/min. In the PJ condition, maximum lactate reached 5.12 mmol/L. Compared with PJ, HRJ resulted in significantly lower lactate levels at 5 and 10 min, as well as a lower peak lactate (mean difference -0.75, p = 0.014). VO{square} at 10 and 30 min and peak VO{square} were also lower with HRJ (peak difference -1.17, p = 0.017). HR showed no significant difference between conditions. ConclusionHRJ reduced peak blood lactate and VO{square}, suggesting suppressed metabolite accumulation and improved exercise efficiency.