Effects of inhalation of the hydrogen-rich gas before sleep on fatigue recovery in healthy adults

Abstract

Our objective was to examine if inhalation of hydrogen-rich gas before sleep can help alleviate fatigue and improve physical performance after waking up in healthy adults. We included 100 healthy adults with no sleep disorders. All participants completed two study visits with a 7-day break. On each of the two, they randomly inhaled either hydrogen-rich (HS) or control gas (CS) for 20 minutes. Each participant completed the assessment of fatigue (e.g., quick recovery, Karolinska Sleepiness scale (KSS)) and functional performance (e.g., Countermovement jump (CMJ), Maximum voluntary isometric contraction (MVIC) and muscle force perception) before inhaling gas and after waking up. No significant difference in the percent change of HRV paraments (i.e., LF/HF, RMSSD, SDNN, LF average, HF average, VLF average) and KSS scale from night to morning were observed between CS and HS (p > 0.67). Similarly, no significant difference in the percent change of CMJ (p = 0.12, Z = 1.55) was observed between CS and HS. Compared to CS, the percent change of MVIC (F = 4.95, p = 0.03, η²=0.03) and muscle force perception (p = 0.01, Z=-2.50) were significantly lower in HS. Inhaling hydrogen-rich gas before sleep can accelerate the recovery of muscle strength and muscle proprioception on the next day in healthy adults.