Total physical activity, activity intensity and body fat in 8 to 11 year old boys and girls (original) (raw)
The relative importance of total habitual activity and time spent at varying intensities of activity to body fatness is unclear. This study examined the relationship between total activity, minutes spent in moderate-to-vigorous physical activity (MVPA) and vigorous activity with percent body fat in 38 boys (mean age, 9.1 ± 0.7 years) and 38 girls (mean age, 9.0 ± 1.0 years). Percent body fat was estimated using dual-energy X-ray absorptiometry. An RT3 accelerometer was worn for 5.2 ± 0.9 days to assess physical activity. Correlations between activity and percent body fat were significant for total activity (boys: r = -0.42, p = 0.009; girls: r = -0.43, p = 0.008) and ≥vigorous activity (boys: r = -0.46, p = 0.003; girls: r = -0.50, p = 0.002). However, there were no relationships between MVPA and percent body fat. Boys in the lowest sex-specific tertile for vigorous activity (≤ 27 minutes) had higher fat than boys in the higher two tertiles (≥ 27 minutes vigorous activity). Girls in the top sex-specific tertile for MVPA (≥ 127 minutes) had lower fat than girls in the lower tertile (≤ 104.5 minutes). In conclusion, total physical activity and time spent in vigorous activity were more strongly related to body fatness than MVPA in 8-11-year-old boys and girls.