The Physical Working Capacity of Normal School Children

The physical working capacity was determined for 243 California school children of both sexes, ranging in age from 6 to 14 years. Working capacity correlated well with the surface area, height, weight, 3-second vital capacity, total vital capacity and age. The 1-second vital capacity and the blood pressures gave relatively poor correlations. The surface area was selected as the variable to be compared with working capacity. Regression lines and 95% confidence bands were determined for each of the sexes. Boys possessed significantly greater working capacities than girls, even at the smaller surface area. Differences became quite marked in the older and larger boys as contrasted with girls of the same age or size. The working-capacity test has a number of advantages over other methods of evaluating physical fitness. It is objective and reproducible and is easily administered with few trained individuals. The results readily permit comparison of various groups and of healthy and diseased individuals.