Effectiveness of Centrifuge-induced Artificial Gravity with Ergometric Exercise as a Countermeasure during Simulated Microgravity Exposure in Humans

摘要

To test the effectiveness of centrifuge-induced artificial gravity with ergometric exercise, 12 healthy young men (20.7 +-1.9 yrs) were exposed to simulated microgravity for 14 days of-6deg head-down bedrest. Half the subjects were randomly selected and loaded 1.2 G artificial gravity with 60 W (four out of six subjects) or 40 W (two out of six subjects) of ergometric workload on days 1, 2, 3,5, 7,9, 11. 12,13,14 (CM group). The rest of the subjects served as the control. Anti-G score, defined as the G-load x running time to the endpoint, was significantly elongated by the load of the centrifuge-ergometer. Plasma volume loss was suppressed (-5.0+- 2.4 vs -16.4+- 1.9%), and fluid volume shift was prevented by the countermeasure load. Elevated heart rate and muscle sympathetic nerve activity after bedrest were counteracted, and exaggerated response to head-up tilt was also suppressed. Centrifuge-induced artificial gravity with exercise is effective in preventing cardiovascular deconditioning due to microgravity exposure, however, an effective and appropriate regimen (magnitude of G-load and exercise workload) should be determined in future studies.