Department of Education, National Defence University, Finland.
J Sci Med Sport. 2010 May;13(3):356-9. doi: 10.1016/j.jsams.2009.04.005. Epub 2009 Jul 1.
The present study aimed to investigate the association between physical fitness, sleep duration and hormonal responses during a 15-day military field training (MFT). The purpose of MFT was to practice offensive manoeuvres in a countryside area. Nine army officers volunteered to participate, and their daily working routine mainly consisted of tasks in the headquarters that required on-call-duty at all times. Physical fitness and body composition were measured just before MFT. Serum testosterone (TES) and cortisol (COR) concentrations and sex-hormone-binding globulin (SHBG) were measured before MFT, as well as 8 and 15 days after the beginning of MFT. Heart rate (HR) was recorded for approximately 24 h on days 8, 11 and 15 of MFT. Based on HR responses, there was no evidence of cardiorespiratory strain, hormonal responses or energy deficit during MFT. Although the changes in hormonal concentrations were insignificant, they were well correlated with physical fitness (r=0.67, p=0.05). Furthermore, the TES/SHGB ratio decreased by 28% in subjects whose VO2max was under 44 ml kg(-1) min(-1). On average, subjects slept for 6.20 h per day, but the sleeping rhythm was disturbed due to military tasks. This diurnal sleeping time was strongly associated with TES/COR ratio (r=0.78, p=0.01). These results indicate that MFT causes very individual stress reactions, despite the low levels of physical strain and energy deficit. We therefore concluded that the observed hormonal responses were mainly due to sleep deprivation and low physical fitness.
本研究旨在探讨体能、睡眠时长与 15 天军事野外训练（MFT）期间激素反应之间的关系。MFT 的目的是在农村地区进行进攻演习。9 名军官自愿参加，他们的日常工作主要包括总部的任务，需要随时待命。MFT 前测量了体能和身体成分。MFT 开始前以及第 8 天和第 15 天测量了血清睾酮（TES）和皮质醇（COR）浓度以及性激素结合球蛋白（SHBG）。在 MFT 的第 8、11 和 15 天，记录了大约 24 小时的心率（HR）。基于 HR 反应，MFT 期间没有证据表明心肺压力、激素反应或能量不足。尽管激素浓度的变化不显著，但与体能高度相关（r=0.67，p=0.05）。此外，VO2max 低于 44 ml kg(-1) min(-1)的受试者 TES/SHGB 比值降低了 28%。受试者平均每天睡眠 6.20 小时，但由于军事任务，睡眠节律受到干扰。这种昼夜睡眠时间与 TES/COR 比值强烈相关（r=0.78，p=0.01）。这些结果表明，尽管体能和能量不足程度较低，但 MFT 会导致非常个体的应激反应。因此，我们得出结论，观察到的激素反应主要是由于睡眠剥夺和低体能所致。
