Changes in lower extremity muscle function after 56 days of bed rest.

摘要: Preservation of muscle function, known to decline in microgravity and simulation (bed rest), is important for successful spaceflight missions. Hence, there great interest developing interventions prevent muscle-function loss. In this study, 20 males underwent 56 days bed rest. Ten volunteers were randomized do resistive vibration exercise (RVE). The other 10 served as controls. RVE consisted contractions against resistance concurrent whole-body vibration. Main outcome parameters maximal isometric plantar-flexion force (IPFF), electromyography (EMG)/force ratio, well jumping power height. Measurements obtained before after rest, including a morning evening assessment on the first day recovery from IPFF (-17.1%), peak (-24.1%), height (-28.5%) declined (P < 0.05) control group. There was trend EMG/force ratio decrease (-20%; P = 0.051). preserved mitigated countermovement jump performance (peak -12.2%; -14.2%). both groups, reduced between two measurements reambulation. This study indicates that rest countermeasure exercises differentially affect various functions skeletal muscle. Moreover, time course during needs be considered more thoroughly future studies, not only with but also within effective maintaining performance. More research needed develop countermeasures maintain strength power.