Esteban DÃaz-Méndez1, Mónica Suárez-Reyes2,3, Rodrigo Fernández-Verdejo3,4
1Escuela de KinesiologÃa, Facultad de Medicina, Universidad Finis Terrae, Santiago, Chile
2Escuela de Ciencias de la Actividad FÃsica, el Deporte y la Salud, Universidad de Santiago, Santiago, Chile
3Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA, USA
4Departamento de Nutrición y Dietética, Escuela de Ciencias de la Salud, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
The relevance of the school setting for the development of physical fitness in male adolescents in Chile
Monten. J. Sports Sci. Med. 2026, 15(2), Ahead of Print | DOI: 10.26773/mjssm.260906
Abstract
The school setting offers adolescents opportunities to engage in physical activity, potentially promoting the normal development of physical fitness. If so, school closure should impair fitness development. We leveraged data from the COVID-19 pandemic to test this idea. We aimed to examine the effects of school closure during the COVID-19 pandemic on the physical fitness of male adolescents from a private school in Chile. Longitudinal records from Physical Education classes were analyzed. The remote-schooling group included 92 boys (median [25th percentile, 75th percentile] age 12.8 [12.5, 13.1] years) measured before school closure due to the pandemic (March 2019) and after reopening (March 2021). The in-person-schooling group included 94 boys (12.7 [12.5, 13.0] years) who were measured in March 2017 and March 2019 and were normally exposed to the school setting. Outcomes included body mass index, maximum oxygen uptake, running speed, sit-ups, standing long jump, and pull-ups. ANOVA was used to test whether changes in the remote-schooling group were different from those in the in-person-schooling group, i.e., group-by-time interactions. Changes in body mass index and pull-ups did not differ between the remote-schooling group and the in-person-schooling group. Nevertheless, compared with the in-person-schooling group, the remote-schooling group showed attenuated increases in maximum oxygen uptake (by 2.5 mL/kg/min), 50-m and 800-m running speed (by 0.4 and 0.8 m/s, respectively), sit-ups (by 4 repetitions), and standing long jump (by 20 cm) (P-interaction < 0.001). School closure thus impaired the normal development of physical fitness in boys from a high socioeconomic background. This highlights the role of schools as health-promoting settings.
Keywords
Physical Activity; Cardiorespiratory Fitness; Obesity; Exercise Test

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