Abstract
Background/Objectives: College student athletes can experience sleep and circadian rhythm disturbances. Methods: A PRISMA-based systematic review about young adult athletes' sleep and circadian rhythms was conducted, with 41 published studies analyzed. Results: Studies suggest that extending sleep duration could enhance athletic performance and support mental health. Risk factors for sleep and circadian rhythm disturbances include early morning practice sessions, late night games, jet lag, and female sex. Consequences of inadequate sleep include reduced reaction times and mental health problems, such as depressive symptoms and anxiety. Across the studies, numerous research design limitations reduced scientific rigor and hindered the ability to test hypotheses about sleep, circadian rhythms, athletic performance, and mental health outcomes. For example, most studies were underpowered due to small sample sizes and missing data. Many studies lacked randomization, control groups, and objective measures of sleep. Researchers commonly failed to control for variables that could confound results (e.g., caffeine, diet, and menstrual cycle hormones). Conclusions: Recommendations for future directions include conducting randomized clinical trials to test interventions related to sleep patterns, nutrition, light exposure, training schedules, and cognitive behavioral therapies to enhance sleep quality. Evidence-based education programs about healthy sleep are essential for coaches and athletes.