Effect of physical training on total and visceral fat in obese children

Children with high levels of total body fat mass (TFM) and visceral adipose tissue (VAT) have elevated levels of certain risk factors for coronary artery disease and non-insulin-dependent diabetes mellitus. We tested the hypothesis that controlled physical training, without dietary intervention, would have a favorable impact on VAT and percent body fat (%BF) in obese children.

A volunteer sample of 74 obese children, 7-11 yr of age, accepted random assignment to physical training or control groups. Before and after 4 months of intervention, measurements were obtained for VAT, TFM, %BF, daily physical activity, and cardiovascular fitness. The intervention involved 4 months of controlled physical training 5 d x wk(-1), 40 min per session, at a mean heart rate (HR) of 157 beats x min(-1). The estimated energy expenditure (EE) per training session was 925+/-201 kJ.

Compared with the control group, the physical training group declined significantly in %BF (delta = -2.2%) (P < 0.01), TFM (delta = -3.1%) (P < 0.01), and subcutaneous abdominal adipose tissue (delta = - 16.1%) (P < 0.05), and increased significantly in fat-free mass (delta = +6.1%) (P < 0.05) and moderate-to-very hard physical activity (delta = +14.1%) (P < 0.05). The increase in VAT was significantly less in the physical training group (delta = +0.5%) as compared with that in the control group (delta = +8.1%) (P < 0.05).

This study showed that during physical training obese children: 1) were capable of participating in a substantial amount of high intensity physical training over a 4-month period: 2) accumulated significantly less VAT as compared with nonexercising controls; and 3) experienced other beneficial changes in total and regional body composition.