Abstract
Physical performance of youth is influenced by various factors, including body composition, biological maturity status, level of habitual physical activity, and muscular strength. Muscular strength has been largely attributed to genetic effects. To exclude possible confounding effects from various acquired factors, this study examined the relationships between polymorphisms of the angiotensin-converting enzyme (ACE), α-actinin-3 (ACTN3), peroxisome proliferator-activated receptor delta (PPARD), and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PPARGC1A) genes and performance as measured by six fitness tests (handgrip strength of dominant hand, 30- and 60-s sit-ups, standing long jump, 60-m dash, and 800-m run) in 170 sedentary adolescent girls with the adjustment of anthropometric characteristics. We found that subjects with the ACE DD genotype were significantly heavier than those with I allele, while those with the ACTN3 RR genotype had higher fat-free mass percentage (FFM%) than those with the XX genotype. In addition, those with the PPARD TT genotype were significantly taller, heavier, and had a greater FFM than those with the CC genotype. Subjects with the ACE DD, ACTN3 RR and PPARD TC genotype had better performance in handgrip strength, 30- and 60-s sit-up tests, and standing long jump, respectively, when individual gene was analyzed independently after adjusting anthropometric characteristics. In the gene combination analysis, subjects with ACE DD, ACTN3 RR and PPARD TT genotype had significantly greater performance in handgrip strength. Overall, the results indicate that the genes studied have a modest influence on individual performance as assessed by specific fitness and strength tests in female late adolescents.