Effects of exercise training with short-duration intermittent hypoxia and hyperbaric exposure on endurance performance and muscle metabolism

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K11410
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 59020:Sports sciences-related
• Research Institution: Hokkaido University of Education
• Principal Investigator: Suzuki Junichi 北海道教育大学, 教育学部, 教授 (80261379)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 間欠低酸素暴露 / 高圧暴露 / ハイブリッドトレーニング / HSP70

Outline of Final Research Achievements

The present study was designed to investigate the effects of short-duration intermittent hypoxia in combination with hyperbaric exposure on endurance capacity and muscle metabolism in well-trained mice. Mice in the training group were housed in a cage with a running wheel for 7 weeks from 5 weeks old. Voluntary running markedly increased maximal work values by 6.0-fold. Trained mice were then subjected to hybrid training with hyperbaric exposure (HYP) for 1 h or both (LOHYP) hyperbaric exposure and intermittent hypoxia for 4 weeks. Maximal endurance capacity was greater in the HYP (by 15%) and LOHYP (by 31%) groups than in the HT group. In white gastrocnemius, activity levels of HAD and CS were significantly higher in the LOHYP group than in the sedentary group. In plantaris, CPT-2 activity levels were significantly higher in the LOHYP group than in the other three groups. The LOHYP procedure substantially upregulated heat shock protein 70 protein levels in hind-leg muscles.

Free Research Field

運動生理学

Academic Significance and Societal Importance of the Research Achievements

本研究は、全身持久力向上を目的とした新たなトレーニング方法の基礎実験を行い、その効果を生理・生化学的、分子生物学的に分析する点で学術的意義が大きい。また、幼若期からトレーニングを積んだマウスへの効果を評価することで、実際の競技スポーツ現場への応用を念頭においている点が特徴的である。高圧暴露と短時間の間欠低酸素暴露をトレーニングに組み込むことによって、骨格筋の脂質代謝の向上とミトコンドリアの酸化的リン酸化が向上することで、持久的運動能力が顕著に向上することが本研究によって明らかとなった。これらの結果は、今後のスポーツ界に新たなトレーニング方法を提案する基礎的データであり、その社会的意義は大きい。