Lifestyle Elements for Improving Mental and Physical Health in Japanese University Students: Subjective Sleep Quality is a Common Key Factor.

This study aimed to reveal the key lifestyle elements that improve physical and mental health in university students by focusing on physical activity, nutrition, and sleep. This cross-sectional study was conducted between October 2021 and December 2021. The participants were 290 first-year students (mean age, 18.63 ± .63 years; age range, 18 to 23; 198 female). The outcomes were daily step counts measured using accelerometers, dietary intake by nutrient category, sleep duration, subjective sleep quality, exercise frequency and duration by exercise type, screen time, depression level, and subjective fatigue by body part. Depression and subjective eye fatigue represent mental and physical health outcomes. Subjective sleep quality predicted depression (β = -1.22, P < .001) and eye fatigue (β = -.23, P < .01) in the path analysis. Participants with higher subjective sleep quality performed more frequent aerobic exercise ( P < .01), longer session times of physical relaxation exercise ( P < .05), and shorter screen time ( P < .05). Subjective sleep quality could be a key factor for high mental and physical health. Furthermore, performing aerobic and relaxation exercises and reducing screen time are important for improving the subjective sleep quality.