Overweight, obesity, steps, and moderate to vigorous physical activity in children

OBJECTIVE: The objective of this study is to establish cutoff points for the number of steps/day and minutes/day of moderate to vigorous physical activity in relation to the risk of childhood overweight and obesity and their respective associations. In addition, we aim to identify the amount of steps/day needed to achieve the recommendation of moderate to vigorous physical activity in children from Sao Caetano do Sul. METHODS: In total, 494 children have used an accelerometer to monitor steps/day and the intensity of physical activity (min/day). The moderate to vigorous physical activity has been categorized according to the public health recommendation (<= 60 versus > 60 min/ day). Overweight or obesity is defined as body mass index > + 1 SD, based on reference data from the World Health Organization. The data on family income, education of parents, screen time, diet pattern, and sedentary time have been collected by questionnaires. Logistic regression and Receiver Operating Characteristic curves have been constructed. RESULTS: On average, boys walked more steps/ day (1,850) and performed more min/ day of moderate to vigorous physical activity (23.1) than girls. Overall, 51.4% of the children have been classified as eutrophic and 48.6% as overweight or obese. Eutrophic boys walked 1,525 steps/ day and performed 18.6 minutes/day more of moderate to vigorous physical activity than those with overweight/obesity (p < 0.05). The same has not been found in girls (p > 0.05). The cutoff points to prevent overweight and obesity in boys and girls were 10,500 and 8,500 steps/ day and 66 and 46 min/ day of moderate to vigorous physical activity, respectively. The walking of 9,700 steps/ day for boys and 9,400 steps/ day for girls ensures the scope of the recommendation of moderate to vigorous physical activity. CONCLUSIONS: In boys, steps/ day and moderate to vigorous physical activity have been negatively associated with body mass index, regardless of race, family income, education of parents, screen time, diet pattern, and sedentary time. We suggest, for steps/day and moderate to vigorous physical activity, studies with different ages and populations, with different designs, so as to inform the cause and effect relationship with various health parameters.