Independent and combined associations between screen time and physical activity and perceived stress among college students

Although both screen time (ST) and physical activity (PA) are associated with stress, independent and combined associations between ST and PA, and perceived stress among college students, have remained unclear. The present study included 1137 undergraduate medical students from a university in Shenyang, Northeast China. PA and perceived stress were measured using the International Physical Activity Questionnaire (IPAQ)-Long Form and the Chinese Perceived Stress Scale (CPSS), respectively. ST and students' characteristics were determined using a self-administered questionnaire. Data were analyzed using the independent t-test, Pearson Chisquared test, and logistic regression. After adjusting for potential confounding factors, females reporting high ST (HST, ST > 6 h/day) were more likely to experience stress than those reporting low ST (LST, ST <= 6 h/day) (OR = 1.557), while those reporting light- and moderate-intensity PA (LMPA) were more likely to experience stress than those reporting vigorous-intensity PA (VIPA) (OR = 1.674). Analysis of the combined effects of PA and ST showed that, among female students, those reporting both LST and LMPA (OR = 2.174), both HST and VIPA (OR = 2.088), and both HST and LMPA (OR = 2.797) were more likely to experience stress compared to those reporting both LST and VIPA (the reference category). The present study confirmed that LST and VIPA were independently and concurrently associated with significantly lower stress among college students, suggesting that promoting PA and reducing ST might be an effective way to reduce perceived stress among college students.