Lung function of healthy boys and girls in Jamaica in relation to ethnic composition, test exercise performance, and habitual physical activity

ABSTRACT

The relationships of forced expiratory volume and forced vital capacity of height, age, sex, area of residence, and ethnic composition were assessed in 622 children in Jamaica. Rural children in hill-farming communities were judged to have a higher habitual physical activity than urban children. Allowing for differences in body size, forced vital capacity averaged 3 percent greater in rural children than in urban children, 7 percent less in girls than in boys, and 16 percent greater in children of European origin than in children of African descent. Lung volumes, indices of gas transfer, and sub-maximal-exercise responses were measured in a subgroup of 108 children of African descent believed to be of common genetic stock. Total lung capacity and vital capacity averaged respectively 6 percent greater and 7 percent greater in rural than in urban children of equal height but residual volume and transfer factor did not differ significantly between localities. Rural children had a lower average cardiac and respiratory components of the oxygen transport system, consonant with the demand for muscular work. Increased habitual physical capacity, total lung capacity, and transfer factor (AU)