Relationships between Depression, Daily Physical Activity, Physical Fitness, and Daytime Sleepiness among Japanese University Students

Abstract

In Japan and other developed countries, the lifestyles of many—particularly the younger generation—have been disrupted in recent years. This disruption may manifest as a decrease in physical activity and deterioration in the quality and quantity of sleep. Depressive tendencies are also increasing among university students. This study examined the relationship between mental health, physical activity, physical fitness, and daytime sleepiness. Eighty-five undergraduate students participated in this study (52 men and 33 women, aged 18.9 (±1.4) years). Physical activity levels were measured using an accelerometer (Lifecorder, Kenz, Nagoya, Japan) for two weeks. To evaluate their level of physical fitness, maximal oxygen uptake (V˙O2max) was calculated by an indirect method using a cycle ergometer. Depressive tendencies and daytime sleepiness were evaluated using the Patient Health Questionnaire (PHQ-9). The PHQ-9 score was positively correlated with sleepiness (r = 0.35, p = 0.001) and total steps per day (r = 0.39, p < 0.001). Moreover, the PHQ-9 score was positively correlated with V˙O2max (r = 0.25, p = 0.019). The PHQ-9 score was higher in students with good exercise habits or part-time jobs. An important finding was the positive correlation between depression and variables related to physical activity levels. These results suggest that vigorous physical activity, such as exercise and part-time jobs, might be positively associated with depressive tendencies among university students.

Physical Activity and Physical Fitness among University Students—A Systematic Review

“…The sample of participants was only female in five studies [ 34 , 38 , 40 , 41 , 43 ], while only one study had male participants only [ 47 ]. There were eight studies where the sample of participants was from the Faculty of Sport and Physical Education students [ 30 , 31 , 33 , 35 , 37 , 40 , 41 , 43 ], only one study had Criminal Police Academy students [ 36 ], while the rest of the studies had participants from different universities and faculties [ 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ].…”

“…Two studies had students from Poland National University [ 45 , 46 ], one had Tsingua University students from China [ 44 ], and all three mentioned were using their own standardized battery test. Aqua-Pilates program [ 40 ], Bamboo dance program [ 39 ], hiking activities [ 35 ], and fitness yoga [ 38 ] were also evaluated and there were also two studies that conducted VO2max evaluation on the treadmill [ 49 ] and cycle ergometer [ 50 ]. The rest of the studies were using standard and already known physical fitness tests.…”

“…Two types of relationships were conducted. The first was the relationship between physical fitness and academic performance among Chinese University students [ 48 ] and the second one [ 50 ] was a relationship between depression, daily physical activity, physical fitness, and daytime sleep time in Japanese University students. In addition, only one study [ 49 ] was determining predictors of metabolic syndrome (eating speed, physical activity and cardiorespiratory fitness) in Korean University students.…”

“…International Physical Activity Questionnaire (IPAQ) was used in four studies [ 42 , 44 , 47 , 48 ] and among those mentioned, only Osipov et al [ 47 ] were using fitness center and sport school documents as evaluation of the physical activity. The self-assessment questionnaire was conducted only by Kaminska et al [ 31 ], Kang et al [ 49 ] had a regular questionnaire, while Shimamoto et al [ 50 ] was the only study that monitored and evaluated physical activity using the accelerometer. Additionally, the mentioned questionnaires are valid and reliable [ 51 , 52 , 53 ], while the details of the accelerometer measurement have already been described in previous studies [ 54 , 55 ].…”

“…Kang et al [ 49 ] found physical inactivity and poor cardiorespiratory function to metabolic equivalent of task risk. Students who are busy with their studies, part-time jobs and extracurricular sport clubs–physical activities that are normally considered to be beneficial [ 69 , 70 ] may cause excessive negative side effects [ 50 ]. In accordance with the current findings, similar results have been found in Western [ 71 , 72 , 73 , 74 ] and Asian countries [ 75 , 76 , 77 ].…”