Objective To monitor daily physical activity level and intensity and to asses the relationship with anthropometrics variables.

Methods 74 subjects (45 females and 29 males) (mean±SD, age 8,61±1,55) were monitored for 3 days. Daily Energy Expenditure (DEE) was measured by SWA and MET (Metabolic Equivalent T) was evaluated. From 74 subjects, 35 were measured for 1 hour of Monitored Physical Activity (MPA). Italian cut-off points for body mass index are used to calculate overweight/obesity prevalence.

Results Negative correlation was found between METS/DEE and age, height, weight, BMI. Not was found significant correlation between METS/MPA and age, height, weight and BMI. Positive correlation was found between METS/DEE and METS/MPA (r2 = 0.26, p<0.002). Difference between METS/MPA and METS/DEE was calculated. Positive correlation was found between this difference and METS/MPA (r2 = 0.78, p<0.000) but not with METS/DEE. Difference was found between DEE/METS of normal weight, overweight and obese children (monofactorial ANOVA, p<0.0049). Significant higher DEE/METS values was found in normal weight respect to obese children (Bonferroni test – p <0.008).

Conclusions Our results suggested that SWA is an useful device to measure energy expenditure. DEE suggest that the most part of children (51/74) consume >2.5 METS and also that BMI and weight affect DEE/METS but no MPA/METS. Physical activity appear a useful tool to increase energy expenditure of all children.