Association of ACTN3 genotypes to performance indicators in brazilian swimming junior athletes specialists in short distances

Abstract

The objective of this research was to identify the genotypic frequency of ACTN3 and to associate it with the technical index(TI) and elite status of 98 juvenile swimmers athletes (16.80 ± 0.63 years) expert in short tests (≤ 200m). A control group (CG) with 101 non-athlete (16.52 ± 0.94 years) was included in the comparisons. The groups were analyzed without division by sex. The athletes were divided by elite competitive experiences (internationals, n = 15) and sub-elite (nacionals n = 83). It was not identified significant differences (X²) in the genotypic frequency between sub-elite and CG athletes. The elite athletes showed supremacy of the RX genotype (60.0%), low frequency RR genotype (13.3%), allele X supremacy (54.2%) and RX + XX addition (86.7%). The adjustment of the genotypic frequencies by the upper quartile (UQ) of the TI revealed that the athletes with RR+RX genotype presented greater average score (806.7 ± 34.8). Elite athletes of the UQ group (RR + RX) showed TI average scores ​​even more expressive (853.9 ± 31.3). The ACTN3 genotypes demonstrated good phenotypeassociation with strength/power only among the athletes identified at the highest levels of performance.