The velocity of motor reaction in humans is a important physical quality to judo competitors. During a high intensity fight, there is a considerable increase in serum lactate, which is closely related to muscle fatigue. This fact may interfere in the capacity of the athlete in reacting to stressful situations during the combat. The main purpose of this work is to study the role of serum lactate increases after a 1'30", 3' and 5' combat situations (Randori) in the velocity of motor reaction in high level judo competitors. METHODS: For this purpose we evaluated 11 healthy male competitors, 23.4 ± 2 years old. To record the simple reaction time, initially, immediately after combat and at the three minutes to rest, we employed the Cybex Reactor System. Serum lactate concentrations was measured by a portable lactate analyser (Accusport). Variance analysis (Kruskal-Wallis) showed significant differences between serum lactate before, immediately after combat and at the three minutes to rest (p < 0.05) and in the velocity of motor reaction (Cybex Reactor), between the number of errors to execute the tests before and after combats (p < 0.05). It was observed a high correlation between the number of errors to execute the tests at Cybex Reactor and the lactate concentration (r = 0.9341). However, it was not found significant differences between the motor reaction time before and after combats (p > 0.05). The results demonstrate that the high serum lactate concentration does not affect the motor reaction time in high level judo competitors, indeed it suggests that there is a decrease in the efficiency of the reaction. This fact was demonstrated by the high correlation found between the lactate concentrations and the number of errors in the reaction tests, probably due to decreases in concentration in judo competitors to stressful situations.
Muscle fatigue; Lactate; Reaction time; Judo
