Development and validation of especific equations for estimate bod

Abstract

Body composition evaluation of youth determined from anthropometric equations is lacking in Brazilian kinantropometry. The aim of this study was to development and validate equations to predict fat percentage in pubescent boys between the ages 10 and 17 years old. This study was descriptive and had with correlational characteristics, the values of body density were computed by Lohman‘s equation, and correlated with variables: age; body weight; stature; eight skinfolds; six circumferences; three diameters and body mass index. One hundred boys were subdivided into two goups, one was the regression group (n = 75) and other was the validation group (n= 25 ) with the same stages of maturity performed by self-assessment. From multiple stepwise regression analyses using SPSS program, equations were developed and validated for the mean of age (13.3± 2.1years). The equation: 0.654252*(Thigh+ Calf ) – 0.002009*(Thigh + Calf )2 was the most adequate model developed with the higher variables correlation r (thigh = 0.858 and calf = 0.855) and lower standard error of estimate: 3.7 % and R2 = 0.90. No diferences were observed with Boileau´s equation (p = 0.605), although it differed from the equations of Mukherjee & Roche and Slaughter (p values of 0.000 and 0.045, respectively). This research suggested the use of this equation with young pubescent boys with similar characteristics to allow for a new reference of percent of body fat in Brazilian boys.