International Journal of Sports Physiology and Performance, 2014, 9, 302 -308 http://dx.doi.org/10.1123/IJSPP.2012-0353 © 2014 Human Kinetics, Inc. www.IJSPP-Journal.com ORIGINAL INVESTIGATION Time–Motion Analysis and Physiological Responses to Karate Official Combat Sessions: Is There a Difference Between Winners and Defeated Karatekas? Helmi Chaabène, Emerson Franchini, Bianca Miarka, Mohamed Amin Selmi, Bessem Mkaouer, and Karim Chamari Purpose: The aim of this study was to measure and compare physiological and time–motion variables during karate fighting and to assess eventual differences between winners and defeated elite karatekas in an ecologi- cally valid environment. Methods: Fourteen elite male karatekas who regularly participated in national and international events took part in a national-level competition. Results: There were no significant differences between winners and defeated karatekas regarding all the studied variables. Karatekas used more upper-limb (76.19%) than lower-limb techniques (23.80%). The kisami-zuki represented the most frequent technique, with 29.1% of all used techniques. The duration of each fighting activity ranged from <1 s to 5 s, with 83.8% ± 12.0% of the actions lasting less than 2 s. Karatekas executed 17 ± 7 high-intensity actions per fight, which corresponded to ~6 high-intensity actions per min. Action-to-rest ratio was about 1:1.5, and high-intensity- action-to-rest ratio was ~1:10. The mean blood lactate response at 3 min postcombat (Lapost) elicited during karate fighting was 11.18 ± 2.21 mmol/L (difference between Lapre and Lapost = 10.01 ± 1.81 mmol/L). Mean heart rate (HR) was 177 ± 14 beats/min (91% ± 5% of HRpeak). Karatekas spent 65% of the time exercising at HR >90% of the individual HRpeak. Conclusion: Karatekas predominantly use upper-limb karate techniques. Karate’s nature is intermittent, with fighting activities representing ~6% of total combat’s duration and ~84% of actions lasting less than 2 s, with ~21-s mean time interval in between. Kumite combat sessions induced high La and near-maximal cardiovascular strain. Other key success factors should be investigated to properly discriminate winners and defeated athletes. Keywords: karate kumite, physiological parameters, activity profile Officially, karate athletes have 3 minutes of combat has 18 ± 6 efforts per 9 ± 6 seconds of recovery pattern to perform different technical and tactical actions.1 (ie, effort:pause ratio of 2:1). Activity phases contained During this time, various arrangements are performed 16.3 ± 5.1 high-intensity actions per fight lasting 1 to 3 intermittently with variations of intensity and constant seconds each, which resulted in 3.4 ± 2.0 high-intensity interruptions being the main characteristic of this combat actions per minute. Furthermore, they reported a post- sport.2–5 There is relatively little scientific evidence deal- combat blood lactate concentration [La] of 7.7 ± 1.9 ing with the physiological requirement of competition. mmol/L. Iide et al3 demonstrated that the duration of the In this context, there are only 2 studies dealing with both shortest offensive and/or defensive techniques was 0.3 ± physiological responses and karate combat analysis,2,3 but 0.1 second for both 2- and 3-minute bouts of combat (ie, they were conducted using simulated fighting conditions. fighting match), while the longest offensive and defensive Beneke et al2 reported that simulated karate competition combination techniques were 2.1 ± 1.0 and 1.8 ± 0.4 seconds, respectively. The total times of offensive and Chaabène is with the Chaabène is with the Tunisian Research defensive techniques during 2- and 3-minute bouts of Laboratory “Sport Performance Optimization,” National Center combat were 13.3 ± 3.3 and 19.4 ± 5.5 seconds, respec- of Medicine and Science in Sport, Tunis, Tunisia. Franchini and tively. In the same study, peak heart-rate responses, [La], Miarka are with the School of Physical Education and Sport, and rating of perceived exertion for both the 2-minute and University of São Paulo, São Paulo, Brazil. Selmi is with the the 3-minute bouts of fighting were 160 ± 12.8 and 169.9 High Inst of Sports and Physical Education, University of ± 9.1 beats/min, 3.1 ± 1 and 3.4 ± 1 mmol/L, and 13.5 Jendouba, Jendouba, Tunisia. Mkaouer is with the Higher Inst ± 1.8 and 15.3 ± 1.7, respectively.3 Rating of perceived of Sports and Physical Education of Ksar Said, Manouba Uni- exertion has been recently established by Milanez et al6 versity, Tunis, Tunisia. Chamari is with the Athletes Health and to be a valid tool in quantifying karate training sessions Performance Research Center, Aspetar, Doha, Qatar. involving basic techniques (kihon) and combat. 302 Time–Motion Analysis and Physiological Responses 303 Thus, since greater understanding of both time– procedures were used in a previous investigation with a motion analysis and physiological parameters of an offi- high reliability and objectivity.9 cial karate combat will assist coaches, scientific experts, Preparatory-activity time began either after the and even athletes in the best way to optimize sport- referee’s hand signal or on termination of the fighting specific training programs and consequently enhance phase, whereas it ended either on the referee’s hand signal karate’s high-level performance, a study conducted in this or when the successive fighting time started. Fighting- combat environment seemed to be needed. Particularly, activity time (FT) was considered an exchange between time–motion analysis is important to applied sport scien- the 2 contestants and began when athletes moved out tists and strength and conditioning coaches to assist in the from the fighting stance toward an exchange and ceased development of game-specific conditioning programs. In once the final execution was ended. More precisely, an addition, research into the physical demands, movement execution finished once the punching limb was retracted, patterns, and combat performance analysis of martial arts kicking foot was returned to the floor, and when contact athletes and more specifically karate is still very limited. between contestants ended. Stoppage activity time was Matsushigue et al7 revealed that winners used fewer started or stopped when the referee called hajime, which tae kwon do techniques during an official tae kwon do means to begin, or yame, which means to stop.1 Stop- competition, while physiological responses (ie, [La] and page period included various events: general—the time heart rate [HR]) did not differ from those of defeated required for the referee to separate contestants after an athletes. Similarly, Roschel et al8 reported no significant exchange, injury—period of time spent when athletes difference in [La] between winners and defeated karate were injured, and penalty/score—the time required when athletes. However, to our knowledge, detailed analysis the referees awarded a penalty or score to a competitor. of combat’s physiological responses and performance All matches were analyzed twice with a 1-week aspects has not been previously reported during official interval between by the same researcher (black-belt and competition in high-level karatekas. Thus, the aims of expert coach) and by a second observer to determine the current study were to verify the relationship between the objectivity of the procedure. The level of agreement performance analysis with physiological responses during between the 2 observations was determined via Cohen official karate combat and to compare winners and kappa statistic as suggested by Landis and Koch.10 Kappa defeated athletes in relation to performance analysis, as values were as following: poor, .0 to <.20; fair, .20 to well as combat physiological responses in a sample of <.40; moderate, .40 to <.60; substantial, .60 to <.80; and high-level karatekas. almost perfect, .80–1.00.10 Cohen kappa between the 2 observations applied to the frequencies of technique used was >.80 (range .85–1), almost perfect. The Student t Methods test showed no significant difference in preparatory (t = 1.75, P = .12), fighting (t = –1.05, P = .33), and stoppage Subjects (t = –.14, P = .89) activity during the 2 analyses of both observers. The intraclass correlation coefficient (ICC) Fourteen male high-level karate athletes (weight catego- was higher than .90 for all phases (preparatory activities, ries: >84 kg, n = 3; <84 kg, n = 2; <75 kg, n = 3; <67 kg, n .96; FT, .90; stoppage activities, .94), showing the high = 3; <60 kg, n = 3) who regularly participated in national reliability of this system. and international events under different weight categories took part in this study (age 21.5 ± 3.1 y, body mass 72.8 Physiological Measurements. Competitors’ HR was ± 10.2 kg, height 180.9 ± 7.8 cm, and karate experi- recorded at 5-second intervals using the Polar Team ence 14.1 ± 2.7 y). All subjects were first-, second-, or System (Team System, Polar, Kempele, Finland). The third-dan black-belt holders. A total of 14 karate combat mean HR (HRmean) was calculated as the average of sessions were analyzed. All athletes provided written the HR during the entire karate combat, while peak informed consent in accordance with the Declaration of HR (HRpeak) was defined as the highest match value. Helsinki. The university ethics committee approved the HRmean was expressed as percentage of the karateka’s 11 study protocol. HRpeak attained during the combat. Intensity effort was classified according to 5 categories: (1) >95% HRpeak, (2) >90–95% HRpeak, (3) >85–90% HRpeak, (4) >80–85% Procedures 12 HRpeak, and (5) ≤80% HRpeak. The time spent, expressed Performance-Analysis Measurements. All combat as percentage of the total combat time, in each category sessions were taped by using 2 Sony cameras (model was calculated. DCR PC 108E, CCD 1000,000 pixels, SSC 1/4000 per s, [La] was measured at rest and at 3 minutes post- Tokyo, Japan).
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