Efeito agudo e crônico de uma atividade condicionante sobre o desempenho da corrida de velocidade de jogadores de futebol profissional

Abstract

OBJECTIVES: Observe the acute (study 1) and chronic effects (study 2) of performing a conditioner activity on performance of thirty meters speed race and muscular architecture component of professional soccer players. METHODS: Eighteen professional soccer players (21 ± 1 years) were randomized in groups of Controls (CON) and Experimental (EXP). The first visits were assigned to familiarize the athletes with experimental procedures and determination of confiability between the days and technical error of variability measures : (1) time of speed race (T30) ; (2) charge of stimulus/training (for 3RM) ; (3) measures of muscular architecture by ultrasonography (US); penance angle (PA); muscular thickness (MT), fascicle length (FL) and determination of basis measures ([BM] measure made for compared with groups CON and EXP). In third and fourth visits, the athletes were submitted randomly to experimental procedures and control. In the group EXP, was performed three maximum repetitions (3MR) of squat in smith machine (conditioner activity CA) and on period between five and six minutes after US images to analyze of muscular architecture. After nine minutes of conditioner activity realization, the athletes were submitted three stimulus in T30. The same procedures were made in the group CON, but without stimulation of CA (Study 1 acute). In third visit, the players were allocated randomly in two groups (CON e EXP), where was started the period of four weeks of training (Study 2 chronic). O EXP performed 3 MRs in squat and after nine minutes were made three stimulus in T30. O CON performed only T30. The athletes performed the training two times a week, totalizing eight sessions of training. At end of training, on eleventh visit, the athletes were submitted to same procedures of beginning of the study. RESULTS: Study 1 The simple ANOVA with repeat measures indicated significant decrease of 6,6 and 6,7% in T30 when compared a condition EXP (3,67±0,17s) vs.CON (3,94±0,18s ) P < 0,002 and EXP (3,67±0,17s ) vs. MB (3,94±0,18s) P < 0,001, respectively, presenting an effect size (ES) of 1,5. Furthermore, there was a significant increase in fascicle length (16,6%, P < 0, 05 [87, 42±14,42mm CON vs. 100, 29±11,56mm EXP]). Study 2 ANOVA 2x2 with repeat measures indicated interaction with group and test, after four weeks of training there was a significant decrease in race time to 15 meters (2,1%, P < 0,001 [1,96±0,09s pre vs. 1,92±0,08s post] ES= 0,5), and 30 meters (3,2%, P < 0,001 [3,92±0,20s pre vs. 3,79±0,18s post] ES=0,6) and significant increased (14,2%, P < 0,001 [90,49±12,04mm pre vs. 102,46±13,11mm post]) in fascicle length. CONCLUSIONS: The CA promoted improvement in race times as well as the acute component of the study and in response to four weeks of training. Likewise, increases were observed only in fascicle length, acutely after CA and at the end of training (chronic)