Predicting Percent Body Fat From Body Mass Index And Triceps Skinfold In Young Athletes

Abstract

PURPOSE: To examine the relationships for percent body fat (%BF) versus body mass index (BMI) and triceps skinfold in young male wrestlers and female swimmers. METHODS: One-hundred twenty-six male wrestlers (mean ± SD age = 14.4 ± 2.2 yrs; body weight = 55.4 ± 15.6 kg; height = 162.2 ± 13.8 cm) and onehundred six female swimmers (mean ± SD age = 15.8 ± 1.2 yrs; body weight = 53.9 ± 6.5 kg; height = 162.1 ± 5.7 cm) volunteered for this study. The subjects performed underwater weighing for the determination of body density and %BF was estimated from body density using the age-specific conversion constants of Lohman. Body weight was measured to the nearest 0.1 kg using a calibrated physician's scale, and height was determined to the nearest 0.1 cm using a wall scale and Broca plane. Skinfold measurements were taken on the right side of the body with a Lange caliper at the triceps site. Simple linear regression was used to examine the relationships for: 1) %BF versus BMI and 2) %BF versus triceps skinfold in males and females separately. RESULTS: The results of the simple linear regression analyses indicated significant (p < 0.05) relationships for %BF (mean ± SD = 11.0 ± 5.7%) versus BMI (20.6 ± 3.4 kg·m-2) in males (r = 0.42, SEE = 5.2%) and females (%BF = 18.5 ± 4.8%; BMI = 20.5 ± 2.2 kg·m-2) (r = 0.70, SEE = 3.4%). In addition, there were significant relationships for %BF versus triceps skinfold in males (9.9 ± 4.1 mm) (r = 0.77, SEE = 3.7%) and females (13.1 ± 3.9 mm) (r = 0.56, SEE = 4.0%). CONCLUSIONS: The findings of the present investigation indicated that predicting %BF from BMI and triceps skinfold resulted in similar SEE values (3.4% vs. 4.0%, respectively) in the female swimmers. For the male wrestlers, however, predicting %BF from triceps skinfold (SEE = 3.7%) may be more accurate compared to BMI (SEE = 5.2%). Thus, these findings suggested that there may be gender-specific differences for the relationships between direct and indirect indicators of body fatness in young, male and female athletes.