Nam Sang-Seok, Park Hun-Young
Taekwondo Research Institute of Kukkiwon, Seoul, Korea.
Department of Sports Medicine and Science of Graduated School, Konkuk University, Seoul, Korea.
Phys Act Nutr. 2020 Sep;24(3):7-12. doi: 10.20463/pan.2020.0015. Epub 2020 Sep 30.
This study was performed to investigate the acid-base and ion balance at rest and after exercise in healthy males under normoxia, moderate hypoxia, and severe hypoxia.
Ten healthy Korean males completed three different trials on different days, comprising exercise under normoxia (FiO2 = 20.9%, N trial), moderate hypoxia (FiO2 = 16.5%, MH trial), and severe hypoxia (FiO2 = 12.8%, SH trial). They undertook endurance exercise for 30 min on a cycle ergometer at the same relative exercise intensity equivalent to 80% maximal heart rate under all conditions. Capillary blood samples were obtained to determine acid-base and ion balance at rest and after exercise.
Exercise-induced blood lactate elevations were significantly increased as hypoxic conditions became more severe; SH > MH > N trials (P = 0.003). After exercise, blood glucose levels were significantly higher in the SH trial than in the N and MH trials (P = 0.001). Capillary oxygen saturation (SCO2) levels were significantly lowered as hypoxic conditions became more severe; SH > MH > N trials (P < 0.001). The pH levels were significantly lower in the MH trial than that in the N trial (P = 0.010). Moreover, HCO3- levels were significantly lower in the SH trial than in the N trial, with significant interaction (P = 0.003). There were no significant differences in blood Na+, K+, and Ca2+ levels between the trials.
MH and SH trials induced greater differences in glucose, lactate, SCO2, pH, and HCO3- levels in capillary blood compared to the N trial. Additionally, lactate, SCO2, and HCO3- levels showed greater changes in the SH trial than in the MH trial. However, there were no significant differences in Na+, K+, and Ca2+ levels in MH and SH trials compared to the N trial.
本研究旨在调查健康男性在常氧、中度缺氧和重度缺氧条件下静息及运动后的酸碱平衡和离子平衡。
10名健康的韩国男性在不同日期完成了三项不同的试验，包括常氧（FiO₂ = 20.9%，N试验）、中度缺氧（FiO₂ = 16.5%，MH试验）和重度缺氧（FiO₂ = 12.8%，SH试验）条件下的运动。在所有条件下，他们以相当于80%最大心率的相同相对运动强度在自行车测力计上进行30分钟的耐力运动。采集毛细血管血样以测定静息及运动后的酸碱平衡和离子平衡。
随着缺氧条件加重，运动诱导的血乳酸升高显著增加；SH > MH > N试验（P = 0.003）。运动后，SH试验中的血糖水平显著高于N试验和MH试验（P = 0.001）。随着缺氧条件加重，毛细血管血氧饱和度（SCO₂）水平显著降低；SH > MH > N试验（P < 0.001）。MH试验中的pH水平显著低于N试验（P = 0.010）。此外，SH试验中的HCO₃⁻水平显著低于N试验，存在显著交互作用（P = 0.003）。各试验间血Na⁺、K⁺和Ca²⁺水平无显著差异。
与N试验相比，MH试验和SH试验在毛细血管血中的葡萄糖、乳酸、SCO₂、pH和HCO₃⁻水平上诱导出更大差异。此外，SH试验中乳酸、SCO₂和HCO₃⁻水平的变化比MH试验更大。然而，与N试验相比，MH试验和SH试验中的Na⁺、K⁺和Ca²⁺水平无显著差异。
