Correlates Of Physical Activity Compliance Rates Among Portuguese Children

The WHO recommends that children engage in at least 60 minutes of moderate-to-vigorous physical activity (MVPA) daily for health benefits. Yet, a significant portion of the population remains inactive. Factors such as age, sex, body mass index, and physical fitness have been linked to non-compliance with MVPA guidelines. Does this scenario start in primary school children? PURPOSE: To answer this question, we first estimated the compliance rates in both sexes across age and then analyzed if, with increasing age, body weight and cardiorespiratory fitness (CRF) levels are associated with compliance. METHODS: Sample comes from the RUSH research project and comprises a random sample of 1,166 Portuguese children of both sexes aged 6-10 y. Based on WHO cut-off points, children’s BMI was divided into two categories: normal weight and overweight/obesity. MVPA was obtained via wrist-worn accelerometry (Actigraph wGT3X-BT) for 7 consecutive days, with a minimum of 4 valid days with at least 10 hours of wear time. CRF was assessed with the pacer test. Binary logistic regression with a school clustering adjustment was used, and the alpha level was 5%. All analyses were done using STATA software. RESULTS: The compliance rate was significantly higher in boys (85.2%) than in girls (67.4%). Logistic Regression showed that with increasing age, children became less likely to comply with MVPA recommendations (OR=0.68, 95% CI=0.59-0.79), but boys were 3 times more likely to comply than girls (OR=3.05, 95% CI=1.57-5.93). Further, the age-by-sex interaction was not significant (p>0.05). Relative to normal weight children, those who are overweight/obese (p>0.05) were not less likely (p>0.05) to comply with the recommendations. However, children with higher CRF levels were more likely to comply (OR=1.06; 95% CI=1.04-1.08). CONCLUSION: Younger children and boys were more likely to comply with MVPA recommendations. Body weight was not associated with compliance, but higher fitness was associated with being more physically active. La Caixa Foundation (SR21-00229)