Document Type



Evaluation of a new instrument for measurement of bioelectric resistance has previously focused exclusively on assessment of body composi­tion in young, healthy men at or near “ideal weight.” A Weight Reduction Trial conducted in Jyvaskyla, Finland provided an opportunity to evaluate the resistance method, both in terms of its relation to other anthropometric dimensions and its ability to predict body composition (percent body fat), in a group of overweight, middle-aged men and women along a continuum of levels of fatness. A series of anthropometric dimensions, bioelectric re­sistance, and underwater volume were measured using standardized tech­niques, and percent body fat (%BF) was estimated from body density. The correlation between replicate resistance measurements was extremely high (r = 0.99). Significant inverse correlations were observed between re­sistance and weight, weight/stature2, body circumferences, and arm muscle area in both sexes, as well as sitting height, biceps and subscapular skinfolds, and body volume in women. Stature2/resistance (S2/R) was positively cor­related in both sexes with all variables except triceps and suprailiac skin- folds, density and %BF (as well as upper arm and hip circumference, and other skinfolds in men). Stepwise and multiple linear regressions demon­strated that for men, hip circumference was the sole predictor of %BF, while S2/R did not significantly contribute to the variance of %BF (Fl 2y = 0.367; p = 0.556), and the model R2 did not change (0.30 versus 0.31). Among women, in addition to hip circumference, thigh circumference, sitting height and age were also significant variables, and accounted for over 56% of the variance of %BF. As observed for men, S2/R did not reduce any of the residual variance of %BF in women (F143 = 0.310; p = 0.587). Based upon these observations, the resistance technique does not appear to con­tribute to the estimation of percent body fat in middle-age, obese individuals.