Validity of skinfold estimates of percent fat in high school female gymnasts

A preseason estimation of body composition may be useful for assigning a safe minimal body weight for female gymnasts. The present investigation examined the validity of 11 skinfold equations for predicting percent body fat (%fat) in high school female gymnasts ((X) over bar age +/- SD = 15.7 +/- 1.2 yr) by comparing the values with those obtained from underwater weighing. Seventy-three gymnasts ((X) over bar %fat +/- SD = 18.6 +/- 4.5%fat) volunteered to serve as subjects. The statistical analyses included examination of the constant error (CE), standard error of estimate (SEE), correlation coefficient (r), and total error (TE). The results of this investigation indicated that 7 of the 11 equations resulted in TE values that were less than or equal to 3.9%fat (range, 3.3-3.9%fat). Of these, the quadratic sum-of-three skinfold equation of Thorland et al. (37) satisfies the most cross-validation criteria and, therefore, is recommended for estimating body composition and minimal body weight in high school female gymnasts. The other six equations with TE values of less than or equal to 3.9%fat should be considered acceptable alternatives.