Application of Molecular Hydrogen as an Antioxidant in Responses to Ventilatory and Ergogenic Adjustments during Incremental Exercise in Humans

• Published in: Nutrients Vol. 13; no. 2; p. 459
• Main Authors: Alharbi, Ahad Abdulkarim D, Ebine, Naoyuki, Nakae, Satoshi, Hojo, Tatsuya, Fukuoka, Yoshiyuki
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 30.01.2021; MDPI
• Subjects: acid status; Acid-base status; Acidosis; Antioxidants; Bicarbonates; Caffeine; Calcium; Carbon dioxide; Crossovers; Deoxygenation; Electrocardiography; Electrolytes; Gas exchange; Gases; Glucose; Hydrogen; hydrogen supplement; Hypoventilation; incremental exercise; Infrared spectra; Infrared spectroscopy; Lactic acid; Measurement techniques; Metabolism; Metabolites; muscle deoxygenation; Muscles; Near infrared radiation; Oxygen consumption; Oxygen uptake; Oxygenation; Placebos; Potassium; Sport science; ventilation; Workload; Workloads; Japan; incremental exercise; muscle deoxygenation; hydrogen supplement; ventilation; acid status
• ISSN: 2072-6643; 2072-6643
• DOI: 10.3390/nu13020459

We investigated effects of molecular hydrogen (H ) supplementation on acid-base status, pulmonary gas exchange responses, and local muscle oxygenation during incremental exercise. Eighteen healthy, trained subjects in a randomized, double-blind, crossover design received H -rich calcium powder (HCP) (1500 mg/day, containing 2.544 µg/day of H ) or H -depleted placebo (1500 mg/day) for three consecutive days. They performed cycling incremental exercise starting at 20-watt work rate, increasing by 20 watts/2 min until exhaustion. Breath-by-breath pulmonary ventilation (V˙ ) and CO output (V˙CO ) were measured and muscle deoxygenation (deoxy[Hb + Mb]) was determined via time-resolved near-infrared spectroscopy in the (VL) and (RF). Blood gases' pH, lactate, and bicarbonate (HCO ) concentrations were measured at rest and 120-, 200-, and 240-watt work rates. At rest, the HCP group had significantly lower V˙ , V˙CO , and higher HCO , partial pressures of CO (PCO ) versus placebo. During exercise, a significant pH decrease and greater HCO continued until 240-watt workload in HCP. The V˙ was significantly lower in HCP versus placebo, but HCP did not affect the gas exchange status of V˙CO or oxygen uptake (V˙O ). HCP increased absolute values of deoxy[Hb + Mb] at the RF but not VL. Thus, HCP-induced hypoventilation would lead to lower pH and secondarily impaired balance between O delivery and utilization in the local RF during exercise, suggesting that HCP supplementation, which increases the at-rest antioxidant potential, affects the lower ventilation and pH status during incremental exercise. HPC induced a significantly lower O delivery/utilization ratio in the RF but not the VL, which may be because these regions possess inherently different vascular/metabolic control properties, perhaps related to fiber-type composition.