Effect of dehydration and core temperature level on athletic performance and anaerobic high and middle power output

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K01720
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Sports science
• Research Institution: Osaka International University (2018); Osaka International College (2016-2017)
• Principal Investigator: Yukio Ogura 大阪国際大学, 人間科学部, 教授 (00300301)
• Co-Investigator(Kenkyū-buntansha): 井上 芳光 大阪国際大学, 人間科学部, 教授 (70144566) ; 近藤 徳彦 神戸大学, 人間発達環境学研究科, 教授 (70215458)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 水分補給 / 深部体温 / 体重減少量 / 無酸素性パワー / 無酸素性持久力 / 運動パフォーマンス / 短距離選手 / 長距離選手

Outline of Final Research Achievements

To examine the effect of dehydration on anaerobic high and middle power output, three experiments were performed: (1) subjects conducted field performance tests with two dehydrated conditions (0.8% and 2.0% of body weight) by fluid intake control during summer athletic practice, (2) In hot condition, subjects performed two tests assessing the anaerobic power output with two dehydrated conditions (0.8 % and 1.9 %), and (3) Sprint and endurance runners performed the same tests as (2) in order to compare different events. (1) Compared to the 0.8% dehydration, the 2.0% dehydration reduced anaerobic middle power performance. Moreover, (2) the decrease of anaerobic high and middle power output in hot condition was greater for the 1.9% dehydration than 0.8% dehydration. However, (3) the effect of dehydration on anaerobic power output was not affected by athletic events. These suggest that the 2.0% dehydration reduces anaerobic high and middle power output.

Free Research Field

スポーツ科学

Academic Significance and Societal Importance of the Research Achievements

これまで脱水が熱放散反応を抑制し，それが深部体温をより上昇することが知られている．本研究では,体重の2％程度の脱水が，ハイパワーやミドルパワー発揮能力にも影響することが示唆された．この結果は，夏季スポーツ活動中の適切な水分補給が，これまで先人が報告してきた熱中症予防のみならず，ハイパワーやミドルパワーに関連するスポーツパフォーマンスの低下を防ぐためにも有効であることを明らかにできた．