Physical activity and body fatness in pre-school children.

The aim of this work was to investigate the relationship between levels of physical activity and body fatness in a group of pre-school children. A cross-sectional study was carried out, physical activity being assessed as the ratio of total energy expenditure/basal metabolic rate (TEE/BMR) and TEE minus BMR. TEE was measured by the doubly labelled water technique, BMR was predicted from body weight. Body fat content was assessed from measurements of total body water via stable isotope dilution. The subjects were 93 children, aged between 1.5 and 4.5 years, in South East England. Measurements of TEE were successful in 77 children. The correlation coefficient between the physical activity level (PAL) values and percentage body fat (sexes combined) was -0.52 (t = 5.3; P < 0.001). This figure indicates that a high level of body fat is associated with a low PAL value and that lower levels of body fat are associated with high PAL values. The correlation coefficient between TEE-BMR and percentage body fat was -0.51 (t = 5.1; P < 0.001). It was concluded that low levels of physical activity in pre-school children are associated with raised levels of body fat.