The Acute Effects of a Single Dose of Molecular Hydrogen Supplements on Responses to Ergogenic Adjustments during High-Intensity Intermittent Exercise in Humans

Abstract

This research examined the effects of single-dose molecular hydrogen (H2) supplements on acid-base status and local muscle deoxygenation during rest, high-intensity intermittent training (HIIT) performance, and recovery. Ten healthy, trained subjects in a randomized, double-blind, crossover design received H2-rich calcium powder (HCP) (1500 mg, containing 2.544 μg of H2) or H2-depleted placebo (1500 mg) supplements 1 h pre-exercise. They performed six bouts of 7 s all-out pedaling (HIIT) at 7.5% of body weight separated by 40 s pedaling intervals, followed by a recovery period. Blood gases’ pH, PCO2, and HCO3− concentrations were measured at rest. Muscle deoxygenation (deoxy[Hb + Mb]) and tissue O2 saturation (StO2) were determined via time-resolved near-infrared spectroscopy in the vastus lateralis (VL) and rectus femoris (RF) muscles from rest to recovery. At rest, the HCP group had significantly higher PCO2 and HCO3− concentrations and a slight tendency toward acidosis. During exercise, the first HIIT bout’s peak power was significantly higher in HCP (839 ± 112 W) vs. Placebo (816 ± 108 W, p = 0.001), and HCP had a notable effect on significantly increased deoxy[Hb + Mb] concentration during HIIT exercise, despite no differences in heart rate response. The HCP group showed significantly greater O2 extraction in VL and microvascular (Hb) volume in RF during HIIT exercise. The HIIT exercise provided significantly improved blood flow and muscle reoxygenation rates in both the RF and VL during passive recovery compared to rest in all groups. The HCP supplement might exert ergogenic effects on high-intensity exercise and prove advantageous for improving anaerobic HIIT exercise performance.

Can molecular hydrogen supplementation enhance physical performance in healthy adults? A systematic review and meta-analysis

“…A gold standard regimen for H 2 application does not appear to exist. The included studies implemented four sources of H 2 , that is, drinking HRW ( n = 18) ( 22–26 , 28–30 , 33 , 34 , 51–53 , 55 , 56 , 58 , 63 , 65 ), HRW bathing ( n = 2) ( 54 , 59 ), inhalation of H 2 -rich gas (HRG) ( n = 5) ( 27 , 57 , 60 , 62 , 64 ), and oral ingestion of H 2 -rich calcium (HRC) powder ( n = 2) ( 31 , 61 ). H 2 concentrations were found to be highly variable (e.g., HRW:0.5 ~ 5.9 ppm; HRG:1 to 68%) among the various products examined.…”

“…Single ( n = 9) or multiple doses (ranging from 3 to 4 doses) of H 2 supplementation prior to exercise is a common intervention protocol. In total, 14 studies examined the effects of H 2 intake within 24 h before exercise ( 23 , 25 , 28 , 29 , 33 , 51 , 53 , 54 , 56 , 58 , 61–64 ). Nine studies implemented the protocol of repeated intake of H 2 from 2 to 14 days before exercise ( 22–24 , 26 , 30 , 31 , 52 , 55 , 57 ).…”

“…In these studies, continuous incremental load and fixed-load subliminal exercise were the most commonly used aerobic endurance intervention or testing protocols. V̇O 2max , V̇O 2peak , TTE, race time, and power were metrics used to measure aerobic endurance performance ( 24 , 26 , 28 , 29 , 33 , 55 , 57 , 61 , 63 ). The 30 s maximal anaerobic power test (i.e., pedaling bicycle or rowing dynamometer) was used to assess the anaerobic endurance (i.e., mean or maximal power) ( 24 , 26 , 27 ).…”

“…One study ( 57 ) used the MVIS to assess the force of knee extension prior to high-intensity aerobic exercise; four studies ( 27 , 30 , 51 , 62 ) were conducted to evaluate the magnitude of knee extensor force or peak torque in the MVIC after vigorous exercise. Eight studies ( 25 , 27 , 30 , 34 , 61 , 63–65 ) evaluated alterations in lower limb explosive power (i.e., CMJ height and peak power output during 10 s or 30 m sprint) during or after vigorous exercise in participants. One study ( 53 ) used the special fitness test to assess the effects of HRW intake on athletic performance in judo athletes.…”

“…Three studies (25,61,65) showed that H 2 can significantly improve lower limb explosive power as compared to the placebo, while another five studies (27,30,34,63,64) showed opposite results that H 2 cannot improve lower limb explosive power (Table 1).…”