Physiological and Biomechanical Fatigue Responses in Karate: A Case Study

Abstract

Knowledge of the fatigue process in karate sport is essential to improve the performance of top athletes. The physiological and biomechanical behavior during the Karate Specific Aerobic Test (KSAT) fatigue protocol in karate was investigated. PCR, lactate, glucose and cortisol were collected before and after the fatigue protocol application in karate, besides that, and heart rate and technical speed were measured. The results indicated increase in C protein reactive (60%), creatine kinase (25%), cortisol (30%), lactate dehydrogenase (90.9%) and decrease in glucose (21.2%). The maximum speed was: in kizami zuki, 5.75 ± 0.31 m/s; in mawashi geri, 9.0 ± 0.24 m/s, in gyako zuki, 7.23 ± 0.54 m/s and in kizami mawashi geri, 6 ± 0.34 m/s. The mean time for each set was 2.99 ± 0.17 s. There was reduction in speed and duration of set for all techniques, especially in the final sets (p<0.05), indicating the presence of fatigue. Gyako zuki was the main blow affected by the phenomenon (p<0.05). Also, the high values observed in biochemical variables after the protocol application indicate metabolic fatigue with muscle damage. Therefore, the athlete adapted his motor behavior in order to hold his technical speed.