Background/Objectives: This study investigates the multifactorial determinants of weight change among Chinese international students in South Korea, focusing on physical activity (PA), sedentary behavior (SB), sleep quality, and psychological stress. Methods: Data were collected from 445 Chinese international students (male = 224, 50.3%) using self-administered questionnaires and follow-up interviews. Participants were categorized into weight gain and weight loss groups based on changes in body weight and BMI. Multinomial logistic regression was used to examine the relationships between lifestyle factors and weight change. Results: The reference group consisted of males and females in the weight loss group. Weight gain was more likely in males experiencing frequent depression (OR = 1.84, p < 0.001), while frequent stress decreased the likelihood of weight gain (OR = 0.24, p < 0.01). Males with weight gain were more likely to experience frequent fatigue (OR = 1.24, p < 0.05) and engage in optimal moderate PA (OR = 1.98, p < 0.05). In females, weight gain was less likely with frequent fatigue and high-intensity PA (OR = 0.25, p < 0.05). Conversely, weight gain was more likely in females with optimal moderate PA and reduced sleep duration (OR = 1.68, p < 0.05; OR = 2.28, p < 0.01). Conclusions: This study identifies gender-specific effects of mental health, PA, SB, and sleep patterns on weight changes among Chinese international students. These findings highlight the need for targeted health strategies addressing mental health, PA, and sleep to support weight management, particularly in international student populations.
Keywords: Chinese students; international students; physical activity; psychological stress; sedentary behavior; weight change.