This research investigated the effect of insomnia caused by military guarding on motor performance and salivary cortisol and testosterone concentration. Some 24 male active-duty soldiers were randomly selected and placed in two groups, insomnia, and control. Insomnia consisted of two hours of guarding with military equipment, two hours of on-call, and two hours of sleep, which started at 4:00 PM and lasted until 6:00 AM the next day. Agility, balance, and reaction time were measured as indicators of motor performance. Saliva samples were collected in the morning two days before, in the morning after applying insomnia, and after measuring motor performance. The results showed that agility performance in the insomnia group was weaker than in the control group. The balance performance of the insomnia group did not differ significantly from the control group. The reaction time in the experimental group was slower when compared to the control group. Although the reaction time was affected significantly, the findings of this research showed that salivary cortisol and testosterone concentration, as well as agility and balance, are not affected by this amount/type of sleep deprivation.
