Military service is a demanding profession that requires high physical preparedness and mental endurance. At the same time, the demands of military duties often require early rising and shortened sleep duration. Such a reduction in sleep can reduce physical and mental performance, and these changes can be reflected in life satisfaction. For this reason, soldiers' life satisfaction is a crucial variable for their success and long-term service. This study examined the relationship between sleep quality, sleep duration, and life satisfaction in military medical students. The results on 35 military students showed that greater sleep quality corresponded to greater life satisfaction; this relationship was moderate and significant (r = -460, p = .005). Notably, participants (n = 17) who began to wake up without the use of an alarm clock reported an average of 11% higher life satisfaction than the participants who woke to an alarm clock; this difference between participants was statistically significant (p = .011, Cohen's d = .911). Pre- and post-intervention showed that sleep hygiene education could be a suitable solution to prevent sleep deprivation and positively impact life satisfaction. Our findings emphasize the importance of increased sleep hygiene education, especially in preparing future military officers and during military exercises. Prioritizing sleep hygiene in these ways can significantly increase soldiers' life satisfaction.

Department of Anthropology and Human Genetics Faculty of Science Charles University Prague Czech Republic

Department of Computer Science Faculty of Electrical Engineering Czech Technical University Prague Prague Czech Republic

Department of Military Medical Service Organisation and Management Faculty of Military Health Sciences University of Defence Hradec Kralove Czech Republic

Department of Neurology General University Hospital Prague Czech Republic

Department of Psychology Faculty of Arts Palacky University Olomouc Czech Republic

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