Relationship between body height and fat-free mass in healthy adults

doi:10.3321/j.issn:1673-8225.2004.15.008

Abstract：AIM: To investigate the relationship between body height and fat-free mass (FFM) in order to derive an approximation formula of FFM in healthy adults.METHODS: Totally 955 healthy adults were divided into obesity group and non-obesity group according to body mass index (BMI) and redivided into two groups by the age of 45, and the relation of FFM with age and obesity was analyzed. Nonlinear regression analysis was performed to assess the allometric relation of FFM with body height.RESULTS: For the healthy adults aged 18-45 years old, the body height was(1.65 ±0.07) m, body mass was(11.28 ±6.75) kg, the fat mass was (11.28 ±6.75) kg, the body fat percentage was(17.91±8.67)%, the FFM percentage was(82.02 ± 8.87)% and the BMI was(22.85 ± 2.99) kg/m2,but for the healthy adults aged 46-74 years old, the body height was ( 1.65 ± 0.07) m, the body mass was(66.08 ± 10.21 ) kg, the fat mass was (14.56 +6.44) kg, the body fat percentage was(22.09 ±9.23)%, the FFM percentage was(77.58 ± 10.07)% and the BMI was(25.19 ± 2.95) kg/m2,the differences were significant ( P ＜ 0.05 ) . There was no significant difference in FFM between those aged 18-45 [(50.93 ± 10.23) kg] and those aged 46-74[(51.53±10.07) kg] (P＞ 0.05) .The values forFFM in healthy adults increased with age and did not differ between obesity and non-obesity groups. The equations obtained by non-linear regression analysis that provided the best approximation of FFM for males was FFM(kg)=24.98 × Height1.68 and for females was FFM(kg) = 22.84 × Height1.42.CONCLUSION: The exponential of body height as a predictor variable can be used to estimate the approximation of FFM.