Promoting active lifestyles in schools. Effect of school day on daily physical activity levels

Introduction: The effect of school day is a major factor in everyday rhythms during childhood and adolescence. The relevance of Physical Activity (PA) in school-aged children raises the need to: (a) analyse whether Primary School pupils achieve the recommended levels of daily PA; (b) find out the impact of school day and, specifically, Physical Education (PE) classes on levels of PA compared to weekends; and (c) explore the differences according to sex in daily PA at these ages. Method: A cross-sectional study was carried out, using a sample of 126 participants (aged 10.2±0.48 years; 51.6% girls, 48.4% boys) from primary schools. Data on the steps taken by pupils during a week were recorded with an ADXK362 three-axis accelerometer integrated into a wristband. Descriptive (means and standard deviation) and inferential analyses (Student’s T-Test) were performed, assuming a 95% confidence interval (p<0.05). The magnitude of the difference was quantified with power (1-β), α=0.05 (bilateral). Results: The average of steps was lower than the minimum recommended, revealing a weekly pattern in which, the most active children were so throughout the week and vice versa. Significant variations were found depending on the days of the week (r=0.40, p<0.001, d= 0.63) or whether they had PE classes (r=0.65, p<0.001, d= 0.79). School day contributed significantly to greater activity and families were less physically active on weekends (t=6.62, p<0.001, d=0.70). Girls had a lower level of PA than boys, and more difficulty reaching the recommended levels of daily PA (t=-4.05, p<0.001, d=0.96), except on weekends. Conclusion: Pupils do not reach the minimum recommended daily steps for their age, with a well-established gender gap in favour of boys. School day (especially when PE is taught) increases their daily PA more than at weekends.