Determinação da frequência genotípica do ACTN3 e da suarelação com o desempenho físico, respostas hormonais eindicadores do dano muscular em jogadores de futebol

Abstract

The objective was to determine the frequency of ACTN3 in soccer players of different categories and their relationship to performance, hormonal responses and indicators of muscle damage after the game. We evaluated 367 male players under- 15 category, sub-17, U-20 and professional and amateur players (N. 14) and a control group (N. 100). All subjects were genotyped for the polymorphism ACTN3- RR, RX and XX. Were applied tests of aerobic capacity, squat jump (SJ), ountermovementjump (CMJ) and sprint test of 30 m (V30) subdivided into 10 m (V10) and20 m (V20). Blood collections were performed in the pre, post, 2 and 4 h after the match and were determined the concentrations of interleukin-6 (IL-6), cortisol, testosterone, ratio testosterone/cortisol (T/C), creatinekinase (CK), muscle alphaactin and between the groups RR/RX and XX. The frequency of ACTN3 in players was not different from control group. However it was noted that the group of professional players had a lower frequency of XX and an increased frequency RX (p<0.05) compared to younger players. Concentrations of CK were higher after the game for both groupsand remained high until the time 4 h (p <0.05) but not different. We identified increased IL-6 post game for the XX group (p <0.05) returning to normal at the time 2 h. There was an increase of testosterone after the game in the group RR/RX that lasted until 4 am (p<0.05). Being that this same pattern was not observed for group XX. In the moments Post, 2 and 4 h testosterone concentrations were higher in RR/RX compared to the group XX. The group RR/RX showed increased levels of cortisol Post the game. In both groups, cortisol concentrationswere lower at times 2 and 4 h compared with the pre (p<0.05), indicating a decrease of concentration. We conclude that the frequency of genotype XX and RX decreasesand increases respectively in older categories in football, indicating a natural selection of individuals of character stronger and mixed in this sport. The RR genotype and allele R is present in more soccer playerswith superior physical performance in tests of strength and speed, while the reverse was not proved in relation to resistance. XX individuals have higher responses of IL-6 to a football game and individuals RR/RX have higher values of markers of CK Postgame.