The Effect of Two Hours Sleep Deprivation at Night on Physical Performance, Blood Levels of Melatonin, Cortisol, and Testosterone in The Military

Sleep deprivation can lead to increased errors, accidents, delays in performance, and doubts about missions and hormonal dysfunction. In some jobs, there are forced sleep deprivation. For example, militaries are deprived of sleep at various times. Therefore, the purpose of the present study was to investigate the effect of two hours sleep deprivation at night on physical performance, blood levels of melatonin, cortisol, and testosterone in the military.

40 military personnel were randomly divided into 4 groups (Group 1: Deprivation of sleep from 12am to 2am; Group 2: Deprivation from 2am to 4am, Group 3: Deprivation from 4am to 6am and Group 4: control group). The protocol consisted of two parts: baseline measurement (before sleep deprivation) which was a pre-test, and post-sleep deprivation measurement. The first part of the study was recorded a week ago of sleep deprivation.

There were significant differences in pre and post-test sleep deprivation 4am to 6am, upper body and lower body strength, explosive power, plasma levels of melatonin, cortisol, testosterone and testosterone to cortisol ratio. Also in sleep deprivation 2am to 4am; significantly changed minimum power, cortisol, testosterone and testosterone to cortisol ratio (p≤0.05).

Maximum physical and hormonal dysfunctions were observed in sleep deprivation 2am to 4am and 4am to 6am.  And doing sensitive work for people and military that have been deprived of sleep during these period times it would not be appropriate.