The purposes of this investigation were to (a) modify the y-intercepts of previously published skinfold (SF) equations using the constant error (CE) values from Stout et al.; (b) cross-validate the modified equations to determine their accuracy for estimating body density (BD) in young wrestlers; (c) derive a new SF equation for estimating BD in young wrestlers, if the modified equations are not found to be accurate; and (d) cross-validate the new SF equation on an independent sample of young wrestlers. One hundred thirty-seven age-group wrestlers (mean ± SD age = 11.3 ± 1.6 year) volunteered to perform underwater weighing for the determination of BD and to have SF measured at 8 sites. Cross-validation of the 16 modified SF equations on a random sample of 50 subjects resulted in total error (TE) values that were 0.0110 g·cm3 (approximately 5.1% fat). Therefore, the following SF equation was derived on a random sample of 100 of the subjects: BD = 1.056-0.00098 (triceps SF) + 0.00132 (age in years) 0.0017 (anterior suprailiac SF) + 0.00031 (body weight in kg). R = 0.78, SEE = 0.0064 g·cm3. Cross-validation of this equation on an independent sample of 37 subjects resulted in a nonsignificant (p > 0.05) CE of 0.0009 g·cm3, a validity coefficient (r) of 0.70, SEE of 0.0076 g·cm3, and TE of 0.0076 g·cm3. Therefore, this SF equation is recommended for estimating body composition characteristics in young wrestlers. Future studies should cross-validate this equation on young athletes in various sports.
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