Physiological demands and time-motion analysis of simulated elite karate kumite matches

[摘要] English: Introduction: Since competition has become the focal point of athletic training and the development of more tournament competitions on both national and international levels, the popularity of karate is ever increasing. No single performance characteristic dominates in combat sports and success requires a mixture of technique, strength, aerobic fitness, power and speed. Thus it has come to light that without proper investigation of the physiological demands imposed on an athlete during a competition situation, it would be unlikely that the athlete will develop to his or her full potential.Objectives: The objectives of this study were:- to identify the various physiological demands placed on the athlete during a simulated karate kumite competition situation;- to conduct a time-motion analysis to determine the characteristics of the karate kumite matches;- to determine the physiological demands imposed on the athlete during simulated competition with regards to the body's energy systems, heart rate response to the fight situation, breathing rates and core temperature.Methods: For this study, twelve (n=12) elite male karate athletes were recruited from the Free State Karate High Performance Squad. Selected tests were performed, including, anthropometry, a graded maximal effort test (VO2max) and a simulated kumite competition. The competition consisted of six rounds with progressively decreasing set recovery periods in between. During the simulated competition, the heart rate, breathing rate and estimated body core temperature were recorded by the Zephyr BioHarnessTM 3 System. All of the kumite matches were video recorded and a time-motion analysis was conducted with the use of Dartfish Software 6, to determine the match characteristics. All physiological and time-motion data were then analysed separately, using a repeated measurements analysis of variance (ANOVA) model with 'round as fixed effect. This analysis excluded the data regarding the techniques scored, which was analysed by a generalized linear model with a Poisson error distribution and logarithmic link function.Results: Athletes achieved a higher HRmax during the simulated kumite matches than during the graded maximal effort test (187.5 < 190.8 bpm). There was a 55.45% aerobic and 44.55% anaerobic energy system contribution during the respective kumite matches, with an effort-to-rest ratio of ~1.5:1. A statistical significant difference (P < 0.05) was found between rounds regarding the means calculated for the mean HR during the fight (F= 7.05; P= 0.03). Fifty-two percent (52%) of all the techniques scored were attributed to upper limb techniques and 48% to the lower limbs. The same values were recorded with regard to the scoring of offensive versus defensive techniques. There were no significant differences (P > 0.05) between rounds with respect to the mean counts of techniques used.Conclusion: A karate kumite match can be characterized as a high-intensity activity with regards to physiological variables, where athletes are subjected to maximal cardiovascular responses. It is thus advisable that coaches remain focussed on the technical and tactical aspects of training and that conditioning specialists focus more on improving the athletes' ability to sustain high-intensity activities during conditioning sessions.

[发布机构] University of the Free State