Prediction of body density and lean body weight in females 25 to 37 years old.

Sixty-one physically inactive females (ages 25 to 37 years) underwent hydrostatic weighing to determine body density (Db). A series of anthropometric measures were also obtained and were used to develop multiple regression equations for the prediction of (Db) and lean body weight (LBW). The anthropometric variables were also used to determine the prediction accuracy of several previously published regression equations. Mean Db was 1.0405 +/- 0.0131 g/ml, relative fat, 25.1 +/- 5.55%, and LBW, 42.14 +/- 4.64 KG. Percentage of body fat was calculated from Db using the formula of Brozek er al. (Am. N.Y. Acad. Med. 110: 113, 1963). Higher correlations were obtained between actual and predicted LBW (R = 0.66 to 0.82). The best regression equation was found to be one using a combination of body weight, one skinfold, and four circumferences. When selected multiple regression equations developed by other authors were used to predict the Db and LBW of the present subjects, the actual values were both over- and underestimated, and correlations between measured and predicted values were lower. It was concluded that even though the body composition of these women was similar to that of college-age women, different regression equations are needed for accurately predicting their Db and LBW.