Barriers to Physical Activity among Full-Time Students: A Case Study during the COVID-19 Pandemic

(1) Background: Physical inactivity is a major public health problem that affects a significant number of adolescents throughout the world. Attaining regular physical activity is a major challenge for adolescents who study full-time. This study aimed to examine the associations between barriers to physical activity, physical activity levels, and time exposed to sedentary behavior during the coronavirus 2019 (COVID-19) pandemic among adolescent full-time students at an institute of professional and technical education. (2) Methods: We employed mixed methods in this case study, which enrolled 119 adolescent students (52.9% of whom were female). More specifically, we applied the Barriers to Physical Activity Questionnaire and the International Physical Activity Questionnaire and conducted semi-structured interviews. Our statistical analysis was based on Poisson regression with robust variance, and our qualitative analysis was based on content analysis. (3) Results: The adolescents frequently presented with a “low” level of physical activity (44.4%, n = 52). The following barriers were associated with a low level of physical activity: lack of time (prevalence ratio (PR) 1.546; confidence interval (CI) 1.111–2.151), lack of motivation (PR 1.573; CI 1.102–2.245), preference for other activities (PR 1.521; CI 1.073–2.155), lack of facilities close to home (PR 1.576; CI 1.077–2.307), laziness (PR 1.463; CI 1.031–2.076), and no way of getting to a facility (PR 1.619; CI 1.005–2.606). (4) Conclusions: We observed that physical activity barriers in the psychological, cognitive, emotional, and environmental dimensions were associated with low levels of physical activity. The students reported that full-time study was a barrier to physical activity that contributed negatively to their physical activity levels and time exposed to sedentary behaviors.