20日間-6°ヘッドダウンベッドレストに伴う宇宙飛行デコンディショニングに対する人工重力および運動負荷の対抗措置としての有効性

摘要

Effectiveness of centrifuge-induced artificial gravity and ergometric exercise as a countermeasure to space deconditioning, including cardiovascular deconditioning, myatrophy, and osteoporosis, induced by 20 days of head-down bedrest., was examined in 12 healthy men. Bedrest was performed with 2300 kcal of diet. Water intake was recommended more than the urine volume in a previous day. A new protocol for artificial gravity with ergometric exercise was adopted, with 1.6 G of artificial gravity and 60 W of exercise every day and 0.3 G artificial gravity with 80％ of maximum oxygen intake. Gravity tolerance was examined by using centrifuge, and anti-G score was determined before and after the bedrest. Not all result has been analyzed, however, effectiveness of artificial gravity with ergometric exercise was evidenced in orthostatic tolerance, physical fitness, cardiac function, myatrophy, and bone metabolism. We concluded this protocol was effective in cardiovascular deconditioning myatrophy, and bone metabolism.%20日間のヘッドダウンベッドレストによる模擬微小重力に伴う心循環系デコンディショニング,筋萎縮，骨粗鬆症に対する対抗措置としての人工重力およびエルゴメーターによる運動負荷の効果について検討した.これまでに低重力負荷+高運動負荷はintensiveに，高重力負荷+低運動負荷はextensiveに行うことが効果的であることは判明していたが，どれくらいの強度と頻度で行うことが有効であるかは不明であった.今回，重力，運動負荷ステップアップ方式によるプロトコールを考案し，その有効性について検討した.本プロトコールによリ，抗G耐性，呼吸循環応答，骨代謝は改善し，その有効性が確認できた.