The validity of visual estimations of percent body fat in lean males

The present study compared the validity of visual estimations of percent fat (% fat) in lean males (mean +/- SD = 9.6 +/- 2.3 % fat) to the validity of bioelectrical impedance analysis (BIA) and skinfold equations. Thirty-five Caucasian male volunteers (mean +/- SD = 23 +/- 5 yr; range = 19-40) served as subjects. Visual estimations of % fat were performed by two experienced male raters. The validity (compared to underwater weighing) for each procedure was determined by examining the constant error (CE), standard error of the estimate (SEE), r, and total error (TE). The results indicated that rater 1 (TE = 2.3% fat) could visually estimate % fat as accurately as the skinfold equations (TE = 2.4% fat). However, based on low TE, SEE, and CE values as well as considerable variability (mean difference = 2.7% fat) between the % fat estimates of the two raters, skinfold equations are recommended over visual inspection and BIA (TE = 5.0% fat) for estimating % fat in lean males.