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Effects of Implementing 15-Minute Physical Exercise Sessions During Physical Education Classes on Physical Fitness
Rodrigo Zanetti da Rocha1, Franciéle da Silva Ribeiro1, Igor Darlan Krause Romig1
1School of Physical Education and Physiotherapy, Federal University of Pelotas (UFPel), Pelotas, RS, Brazil.
Background:
The prevalence of overweight, obesity, and low physical fitness is associated with minimal engagement in physical exercise (PEx) and has increasingly affected children and adolescents in rural areas. This study examines the effects of a 15-minute PEx intervention on the levels of physical fitness and anthropometric indicators of overweight and obesity among rural school students.
Methods:
A total of 245 school students (135 boys and 110 girls), aged between 11 and 17 years, were randomly allocated into intervention and comparator groups. The intervention lasted for 12 weeks, comprising 24 PEx sessions. Physical fitness was measured through cardiorespiratory fitness, muscular strength/endurance, handgrip strength, lower limb power, flexibility, speed, and agility. The measured anthropometric indicators of overweight and obesity included body mass index, waist circumference, and the sum of subscapular and triceps skinfolds.
Results:
Generalized estimating equations analysis, performed with an intention-to-treat approach, indicated significant group × time interaction (P < .05) for flexibility, muscular strength/endurance, handgrip strength, cardiorespiratory fitness (only for boys), and waist circumference. For these 5 variables, there were no differences between groups at the baseline (P > .05), and the intervention group showed significantly greater improvements compared with the comparator group at the postintervention time (P < .05).
Conclusion:
An intervention program consisting of 15 minutes of PEx during PE classes, conducted twice a week for 12 weeks, improves cardiorespiratory fitness, flexibility (only for boys), muscular strength/endurance, handgrip strength, body mass index (only for girls), and waist circumference of rural adolescent school students.
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