Physical activity level measured by accelerometry and physical fitness of schoolchildren / Nível de atividade física mensurada por acelerometria e aptidão física de escolares

Abstract Objective: To describe and compare physical fitness variables according to compliance with the recommendations of physical activity, measured by accelerometry. Methods: The sample gathered 120 students, 57 boys and 63 girls aged 9 to 11 years. The variables analyzed were: weight, stature, BMI, skinfolds, waist circumference, agility, flexibility, speed and strength of upper and lower limbs, and abdominal strength. Physical activity was measured objectively using an accelerometer. The students were divided into two groups: "complies with recommendations" (≥60min/day) and "does not comply with recommendations" (<60min/day). To verify the normality of the data, the Kolmogorov-Smirnov test was used. The mean values of students who do or do not comply with the physical activity recommendation were compared using Student's t and U-Mann Whitney tests. The level of significance was set at p<0.05. Results: The students who followed the recommendation showed significantly lower values compared to those who did not for adiposity (sum of 7 skinfolds); body weight; body mass index (BMI) and abdominal strength. No significant differences were found in the variables of speed and agility, and the upper limbs' strength was greater in subjects who did not comply with recommendations. Conclusions: Students who complied with physical activity recommendations had better body composition and more abdominal strength than those who did not.

RESUMO Objetivo: Descrever e comparar as variáveis da aptidão física de acordo com o cumprimento da recomendação de atividade física, medida por acelerometria. Métodos: A amostra foi composta de 120 escolares, sendo 57 meninos e 63 meninas, de 9 a 11 anos de idade. As variáveis analisadas foram: peso, estatura, índice de massa corpórea (IMC), dobras cutâneas, circunferências, agilidade, flexibilidade, velocidade e força de membros superiores, inferiores e abdominal. A atividade física foi mensurada de forma objetiva por meio de acelerômetro. Os escolares foram divididos em dois grupos: "cumpre a recomendação" (≥60min/dia) e "não cumpre a recomendação" (<60min/dia). Para verificar a normalidade dos dados, foi utilizado o teste de Kolmogorov-Smirnov. A comparação dos valores médios dos escolares que cumprem ou não a recomendação de atividade física foi feita pelos testes t de Student e U de Mann-Whitney. O nível de significância adotado foi de p<0,05. Resultados: Os escolares que cumpriram a recomendação, comparados com os que não cumpriram, apresentaram valores significativamente menores para adiposidade (somatória das sete dobras cutâneas), peso corporal, IMC e força abdominal. Não foram encontradas diferenças significativas nas variáveis de velocidade e agilidade; quanto à força de membros superiores (MMSS), constatou-se que ela foi maior em quem não cumpriu a recomendação. Conclusões: Crianças que cumpriram a recomendação de atividade física apresentaram melhor composição corporal e força abdominal que as crianças que não cumpriram.

Physical activity level measured by accelerometry and physical fitness of schoolchildren.

OBJECTIVE: To describe and compare physical fitness variables according to compliance with the recommendations of physical activity, measured by accelerometry. METHODS: The sample gathered 120 students, 57 boys and 63 girls aged 9 to 11 years. The variables analyzed were: weight, stature, BMI, skinfolds, waist circumference, agility, flexibility, speed and strength of upper and lower limbs, and abdominal strength. Physical activity was measured objectively using an accelerometer. The students were divided into two groups: "complies with recommendations" (≥60min/day) and "does not comply with recommendations" (<60min/day). To verify the normality of the data, the Kolmogorov-Smirnov test was used. The mean values of students who do or do not comply with the physical activity recommendation were compared using Student's t and U-Mann Whitney tests. The level of significance was set at p<0.05. RESULTS: The students who followed the recommendation showed significantly lower values compared to those who did not for adiposity (sum of 7 skinfolds); body weight; body mass index (BMI) and abdominal strength. No significant differences were found in the variables of speed and agility, and the upper limbs' strength was greater in subjects who did not comply with recommendations. CONCLUSIONS: Students who complied with physical activity recommendations had better body composition and more abdominal strength than those who did not.