Universities Space Research Association, Houston, TX.
University of Houston, Houston, TX.
Med Sci Sports Exerc. 2018 Sep;50(9):1920-1928. doi: 10.1249/MSS.0000000000001618.
This study investigated the safety and effectiveness of a new integrated aerobic and resistance exercise training prescription (SPRINT) using two different sets of exercise equipment: a suite of large International Space Station-like exercise equipment similar to what is found on the International Space Station and a single device with aerobic and resistance exercise capability in the spaceflight analog of bed rest (BR).
Subjects (n = 34) completed 70 d of 6° head down tilt BR: 9 were randomized to remain sedentary (CONT), 9 to exercise training using traditional equipment (EX), 8 to exercise using traditional equipment and low-dose testosterone supplementation (ExT), and 8 to exercise using a combined resistance and aerobic flywheel device. Peak aerobic capacity, ventilatory threshold, cardiac morphology and function (echocardiography), muscle mass (magnetic resonance imaging) and strength/power (isokinetic, leg press, and vertical jump), and bone health (bone mineral density, blood and urine bone markers) were assessed before and after BR.
The SPRINT protocol mitigated BR-induced muscle and cardiac deconditioning regardless of the exercise device used. Molecular markers of bone did not change in the CONT or EX groups. Peak aerobic capacity was maintained from pre- to post-BR in all exercise groups similarly, whereas significant declines were observed in the CONT group (~10%). Significant interaction effects between the CONT group and all EX groups were observed for muscle performance including leg press total work, isokinetic upper and lower leg strength, vertical jump power, and maximal jump height as well as muscle size.
This is the first trial to evaluate multisystem deconditioning and the role of an integrated exercise countermeasure. These findings have important implications for the design and implementation of exercise-based countermeasures on future long-duration spaceflight missions.
本研究调查了一种新的综合有氧和抗阻运动训练方案（SPRINT）的安全性和有效性，该方案使用了两套不同的运动设备：一套类似于国际空间站的大型国际空间站式运动设备，以及一种具有有氧和抗阻运动能力的单一设备，可在卧床模拟的空间飞行中使用（BR）。
受试者（n = 34）完成了 70 天的 6°头低位倾斜 BR：9 名被随机分为保持久坐（CONT）、9 名使用传统设备进行运动训练（EX）、8 名使用传统设备和低剂量睾酮补充剂进行运动训练（ExT），以及 8 名使用组合式抗阻和有氧飞轮设备进行运动训练。在 BR 前后评估了峰值有氧能力、通气阈值、心脏形态和功能（超声心动图）、肌肉质量（磁共振成像）和力量/功率（等速、腿举和垂直跳跃）以及骨骼健康（骨密度、血液和尿液骨标志物）。
无论使用何种运动设备，SPRINT 方案都能缓解 BR 引起的肌肉和心脏适应性下降。CONT 或 EX 组的分子骨标志物没有变化。所有运动组的峰值有氧能力均从 BR 前保持到 BR 后，而 CONT 组则出现显著下降（~10%）。在 CONT 组和所有 EX 组之间观察到肌肉表现的显著交互作用，包括腿举总功、等速上下肢力量、垂直跳跃功率和最大跳跃高度以及肌肉大小。
这是第一项评估多系统适应性下降和综合运动对策作用的试验。这些发现对未来长时间航天飞行任务中基于运动的对策的设计和实施具有重要意义。
