Rummel J A, Michel E L, Sawin C F, Buderer M C
Aviat Space Environ Med. 1976 Oct;47(10):1056-60.
Preflight, inflight, and postflight exercise response tests were conducted on the astronauts of the second Skylab mission (Skylab 3) as part of an evaluation of physiological adaptation to long-term weightlessness. The flight phase of this mission was 59 d in duration. An exercise protocol was designed around a bicycle ergometer which was used to apply work loads approximating 25, 50, and 75% of each crewman's measured maximum aerobic capacity (VO2 max). Respiratory gas exchange (VO2, VCO2, and VE), heart rate, and blood pressure were measured during all tests; cardiac output was measured at selected times during preflight and postflight tests. Data obtained both at rest and during exercise in flight showed no consistent changes which would indicate a degraded physical work capacity. In fact, heart rate during exercise actually decreased for all crewmen in flight. This response indicated improved physical fitness in flight relative to preflight. The improved physical condition of this crew relative to that of the first Skylab crew is attributed to frequent performance of high levels of aerobic exercise in flight. The postflight period of readaptation of 1 G was characterized by a marked tachycardia, during which time stroke volume was decreased. This response returned to normal within 5 d postflight.
作为对长期失重生理适应性评估的一部分，对第二次天空实验室任务（天空实验室3号）的宇航员进行了飞行前、飞行中和飞行后的运动反应测试。此次任务的飞行阶段时长为59天。围绕一台自行车测力计设计了一项运动方案，该测力计用于施加相当于每名机组人员测得的最大有氧能力（最大摄氧量）25%、50%和75%的工作量。在所有测试过程中均测量呼吸气体交换（摄氧量、二氧化碳排出量和每分钟通气量）、心率和血压；在飞行前和飞行后的测试过程中的选定时间测量心输出量。在飞行中休息和运动期间获得的数据均未显示出表明体力工作能力下降的一致变化。事实上，飞行中所有机组人员运动时的心率实际上都下降了。这一反应表明飞行中的体能相对于飞行前有所改善。该机组人员相对于第一批天空实验室机组人员体能状况的改善归因于在飞行中频繁进行高强度有氧运动。1G再适应的飞行后阶段的特点是明显的心动过速，在此期间每搏输出量减少。这种反应在飞行后5天内恢复正常。
