THE ACE I/D POLYMORPHISM AND BODY DIMENSIONS IN STRENGTH ATHLETES VERSUS CONTROLS

Abstract

Recently about 10 studies reported on the association of the Angiotensin Converting Enzyme (ACE) Insertion/Deletion (I/D) polymorphism with several characteristics of human performance. The underlying specific body composition in athletes could in part explain this (lack of) association. This study therefore investigated the ACE I/D polymorphism in 50 male national and international level Body Builders and weight lifters (BB) with 58 control subjects (sedentary or moderately physical active) (CO). BB had a significantly higher body weight, BMI, limb circumferences, and mesomorphy component, smaller extremity skinfolds and on average twice as large muscle+bone arm area compared to CO. The allele frequency in the total group was 0.42 for the I and 0.57 for the D allele, and observed genotype frequencies were in Hardy-Weinburg equilibrium (Chi2: 0.1, P = 0.75). Chi2 tests showed no evidence for association of the ACE I/D polymorphism with athlete or control status (Chi2, 2df: 0.94, P = 0.62 for genotype association, Chi2, 1df: 0.83, P = 0.36 for test of dominance of the I allele). Association between genotype and body dimensions was further studied using analysis of covariance with age and weight as covariates. Association of the ACE I/D genotype was only suggestive for indicators of subcutaneous and overall adipose tissue. Carriers of the I/I genotype had significantly smaller suprailiacal skinfolds, lower percentage fat and absolute fat mass, a higher fat free mass and a lower score on endomorphy compared to I/D and D/D genotypes (F-values ranged 2.97–2.30, P values 0.06–0.10). This study indicates no significant role of the ACE I/D polymorphism in explaining differences in muscularity and body composition between Body Building athletes and controls. It therefore does not add to the evidence of the ACE gene as associated with human performance. The underlying mechanism might be more related to a healthier cardiovascular system than to muscle mass or a strength component.