association between objectively measured physical activity and sedentary behavior with body composition among primary school children

Background: physical activity (pa) plays a crucial role in the overall well-being of children in the long term. the present study aimed to investigate the correlation between pa, sedentary behavior (sb), and body composition (bc) among primary school children.methods: this descriptive-correlational study was conducted in ali-abad-katoul, iran in 2023. a sample size of 322 boys was selected using convenience sampling method. actigraph wgt3x-bt accelerometer and body composition x-scan plus ii were used for measuring pa pattern and bc. pearson correlation and independent t tests were used to analyze the data.results: the accelerometer data revealed that participants spent 67.55% of the total time in sb. moreover, on average, daily moderate-to-vigorous physical activity (mvpa) was 49.71±22.37 minutes. accordingly, the daily energy expenditure was 558.39±250.17 kcal. sb was directly and significantly associated with body mass index (bmi) (r=0.628, p<0.001) and mass of body fat (mbf) (r=0.347, p<0.001). in addition, our results revealed an inverse and significant correlation between mvpa with bmi (r=-0.849, p<0.001) and mbf (r=-0.716, p<0.001). finally, the children who did meet the mvpa guideline had significantly lower bmi (t=-3.781, p<0.001) and mbf (t=4.892, p<0.001) and higher skeletal muscle mass (smm) (t=4.209, p<0.001) than those who did not meet the mvpa guideline.conclusions: these findings suggested that vigorous pa and sb play a role in controlling children’s adiposity, highlighting the importance of engaging children in high-intensity pa and reducing sb.