Taekwondo has been an Olympic combat sport since the 2000 Sydney Olympic Games (4). Competitions are held at the regional, national, and international levels, and are organized according to gender and weight categories (4) and conducted according to a single elimination tournament system. Winners of preliminary phases of bouts progress to successive phases (qualifying, quarterfinal, and semifinal) until the final bout of the championship.
One bout consists of three 2-minute rounds, with a 1-minute rest period between rounds. Taking into account the fact that physiological demands on the taekwondo competitors vary over the course of a bout (2,3,5,9,28), various authors have analyzed the tactics used over the 3 rounds (2,4,9,14,15,19,24,34,35). Those researchers found that, in general, the number and duration of tactical actions performed by taekwondo athletes vary during the bout, with longer and more frequent periods of action during the third round than in the previous ones (2,14,15,19,34,35). This may be because athletes tend to use the first 2 rounds to evaluate their opponents and to conserve energy for the final part of the bout (2).
In the literature, the use of attacks and counterattacks during bouts has been examined to reveal tactics of elite competitors (4). To win a bout, taekwondo athletes perform offensive tactical actions, which are the only way to score (14). Offensive actions are divided into attacking actions (initiated by the athlete) and counterattacking actions (in response to an opponent's attack) (16). Attacking actions can be classified as direct or indirect, whereas counterattacking actions can be anticipatory, simultaneous, or posterior (16).
Previous studies have shown that taekwondo tactics used by variety of athletes (international-, cadet-, and university-level competitors) are characterized by attacks rather than by counterattacks (4,11,12,14,15,19,22,27,30). In fact, at the Olympic level, attacks appeared to be the most effective actions reported during the Sydney (2000) and Athens (2004) Olympics (20,24), whereas the opposite trend was observed during the Beijing (2008) Olympics (8,23). That is, counterattacks appeared to be the most effective. Similar tactics can be observed among young and international athletes (at the World Championships) who use more counterattacking actions to score (14,36). According to the classification of tactical actions, direct attack and simultaneous counterattack seems to be the most common and effective actions during competitions (14).
Regarding the frequency of actions, previous studies have analyzed and sought to improve athletes' performance by analyzing factors that could affect their tactics (i.e., laterality [14,30], gender [4,12,20,24,25,30,35], weight category [20,24,30,35], and match outcome [4,11,24,25,30,35,36]) and allow them to emulate and counter the tactics of opponents. Such studies revealed little (30) or no difference in athletes' tactics (4,12,14,20,24,25,30,35). On the contrary, studies that analyzed tactics according to the match outcome by comparing winners and nonwinners showed that winners perform fewer actions but achieve higher scores than nonwinners (22,29,36) do. Specifically, winners performed fewer attacks and more counterattacking (25,36); they specifically used indirect attacks and anticipatory counterattacks (11).
Some authors have hypothesized that other factors could influence the tactics of competitors, especially at the end of a bout. These include the greater energy required for high-intensity actions (kicks) (9), the increased frequency of these actions as a match progresses (2,14,15,19,34,35), and the more-decisive actions that can affect the match outcome during the last round (5). This suggests a need to continue studying those factors, which could help coaches to understand and explain the best performance (from winners). Such analyses of winners would assist athletes and coaches in reviewing and comparing strategies to achieve success in taekwondo (20,25).
Thus, the aim of this study was to analyze the tactical behavior of taekwondo athletes (direct and indirect attacks, in addition to anticipatory, simultaneous, and posterior counterattacks) according to rounds (first, second, and third), and in each match between competitors (winners and nonwinners) in a university taekwondo championship. It has been hypothesized that technical and tactical variables differ throughout bout and within each round, and these affect match outcome. Specifically, nonwinning athletes may use a wide variety of kicking techniques, yet demonstrate limited tactical capability. This would allow coaches to construct an activity profile for athletes in relation to typology of actions, rounds, and match outcomes that could help them to structure training appropriately.
Experimental Approach to the Problem
To test the hypothesis, an observational analysis of athletes' tactical behavior in each round was conducted in relation to match outcome and in each round. The literature (12,30) provides information on the tactical aspects and considers the typology of tactics used by competitors (i.e., attacking and counterattacking actions), round of a bout (i.e., first, second, and third), and match outcome (winning and nonwinning).
Regarding the tactical aspects, attacking actions can be classified as direct or indirect, whereas counterattacking actions can be anticipatory, simultaneous, or posterior. A direct attack is a kick that is not preceded by another movement. An indirect attack is a kicking action preceded by another movement to disguise the intent to kick. An anticipatory counterattack is a kicking action performed during the preparatory or initial phase (raising of the leg) of an opponent's attack. A simultaneous counterattack is performed when the attacking athlete's leg is at the end of the initial phase (lifting) or at the same time as the attacker's kick. Finally, a posterior counterattack is a kicking action performed after the attacker's kick, when the attacking leg is falling (16).
Concerning match outcomes, the participants were grouped as winners or nonwinners according to the outcome of each bout in every phase of competition (qualifying, quarterfinal, semifinal, and final phases).
This study included 204 university taekwondo athletes. This competition counted for selection for the Universiade 2011 Championship, Shenzhen, China. To enter, competitors had to hold the rank of brown or black belt and be 18–33 years of age (7). For that, national championships attract very experienced black-belt athletes who have participated in several international and national championships and less-experienced brown-belt athletes. Four performances by losing athletes were excluded from the analysis because they were extremely atypical. According to The Belmont Report (37) and competition regulations (39), because the videotapes that were analyzed for this study are in the public domain, it is not necessary to obtain informed consent from participants. The Belmont Report describes basic ethical principles and guidelines concerning ethical issues of research with human subjects. According to the guidelines, images of public behavior may be used for research without the informed consent of athletes.
A total of 334 performances in 169 bouts in the National University Championship were obtained of the official videotapes recordings (Logitech HD Webcam c525; Logitech, Zurich, Switzerland). The cameras were placed on the referees' table to record all bouts, which allowed video replay and observational analysis (11).
In line with previous studies (4,12,19,20,24,27,30,34), an observational methodology was followed. A single observer viewed the video recordings (1). The reliability of the data (intraobserver and interobserver, compared with an expert observer researcher) was calculated using Cohen's Kappa coefficients, with a confidence interval of 95%, for the analyses of 5 randomized matches (33). The Kappa coefficient exceeded 0.70 for all study variables (Table 1), which showed that scoring was highly reliable (13,26). Analyses of the videos were performed using IT program (University of Málaga, Málaga, Spain) (18).
Statistical analyses were conducted using SPSS software (17.0; SPSS, Inc., Chicago, IL, USA). The preliminary (Kolmogorov–Smirnov) analysis showed a normal distribution of all the variables considered. A 2-way repeated measure analysis of variance was conducted, with “round” (at 3 levels: first, second, and third) as a within-subject factor, and match outcome (at 2 levels: winning and nonwinning) as the between-subject factor. Partial eta squared (
) values below 0.01, 0.01–0.06, 0.06–0.14, and >0.14 were considered trivial, small, medium, and large effect sizes, respectively (6). Greenhouse-Geisser correction provided a more conservative analysis where necessary to compensate for violations of the sphericity assumption. The alpha level was set at 0.05 for all statistical analyses. Significant main factors and interaction effects were subsequently examined using the Bonferroni adjustment for multiple comparisons.
A main effect was observed for “round” in direct actions [F(332,1) = 21.25; p = 0.01;
] and anticipatory actions [F(332,1) = 8.56; p = 0.01;
]. That is, taekwondo athletes performed fewer direct actions in the first (4.98 ± 3.04) than in the second (5.43 ± 3.43) (p = 0.04) or third rounds (6.00 ± 4.00) (p = 0.001), and fewer in the second (5.43 ± 3.43) than in the third round (6.00 ± 4.00) (p = 0.03). Moreover, they performed fewer anticipatory actions in the first round (0.45 ± 0.83) than in the third (0.64 ± 1.06) (p = 0.01). Results are presented in Table 2.
A main effect was observed for winning vs. nonwinning in indirect actions [F(332,1) = 11.35; p = 0.01;
] and anticipatory actions [F(332,1) = 18.09; p = 0.001;
]. Specifically, the results showed that winners perform fewer indirect (5.73 ± 4.07) (p = 0.001) and more anticipatory actions (2.03 ± 2.20) than nonwinners do (7.20 ± 5.29 and 1.09 ± 1.60, indirect and anticipatory, respectively) (p = 0.001).
A significant interaction effect was found for round and outcome, in direct [F(332,1) = 20.05; p = 0.01;
], indirect [F(332,1) = 21.82; p = 0.01;
], anticipatory [F(332,1) = 9.67; p = 0.01;
], simultaneous [F(332,1) = 13.23; p = 0.001;
], and posterior [F(332,1) = 2.99; p = 0.01;
] tactical actions.
Specifically, there were significant differences between winners and nonwinners in direct actions [F(332,1) = 9.80; p = 0.002;
] and indirect actions [F(332,1) = 31.06; p = 0.001;
] in the third round, in anticipatory actions in the second round [F(332,1) = 15.64; p = 0.001;
] and third round [F(332,1) = 17.62; p = 0.001;
], in simultaneous actions in the first round [F(332,1) = 4.67; p = 0.03;
] and third round [F(332,1) = 4.38; p = 0.04;
], and in posterior actions in the third round [F(332,1) = 5.84; p = 0.02;
]. That is, winners perform fewer direct (p = 0.002) and indirect (p = 0.001) actions (5.33 ± 3.54 and 1.62 ± 1.59, respectively) than nonwinners (6.68 ± 4.33 and 2.90 ± 2.52, respectively) do in the third round. Winners perform more anticipatory actions (0.69 ± 0.99) than nonwinners (0.32 ± 0.66) do in the second (p = 0.001) and the third (p = 0.001) rounds (0.88 ± 1.18 and 0.40 ± 0.86, respectively, for winners and nonwinners). Winners perform fewer simultaneous actions than do nonwinners in the first (0.58 ± 0.82 and 0.81 ± 1.12, respectively, for winners and nonwinners) round (p = 0.03) and more in the third (0.88 ± 1.12 and 0.63 ± 1.08, respectively, for winners and nonwinners) round (p = 0.04). Finally, winners perform more posterior actions (1.91 ± 1.78) than do nonwinners (1.47 ± 1.57) in the third round (p = 0.02).
Subsequent Bonferroni comparisons between tactical actions performed by winners and nonwinners in each of the 3 rounds showed differences for nonwinners in direct actions between the first (4.65 ± 3.03) and second (5.44 ± 3.49) rounds (p = 0.01), the first and third (4.65 ± 3.03 and 6.68 ± 4.33, respectively) rounds (p = 0.001), and the second and third (5.44 ± 3.49 and 6.68 ± 4.33, respectively) rounds (p = 0.001). There were also differences in the number of indirect actions between the first (2.04 ± 2.00) and second (2.39 ± 2.15) rounds (p = 0.003), and the first and third (2.25 ± 2.19) (p = 0.001) rounds. Meanwhile, winners showed differences in the number of indirect actions between the second (2.16 ± 1.90) and third (1.62 ± 1.59) (p = 0.01) rounds, in anticipatory actions between the first (0.48 ± 0.85) and second (0.69 ± 0.99) (p = 0.02) rounds, and between the first and third (0.88 ± 1.18) (p = 0.001) rounds, and in simultaneous actions between the first (0.58 ± 0.82) and third (0.88 ± 1.12) rounds (p = 0.004).
In terms of scientific research, this study is one of the first to evaluate tactics (direct and indirect attacks and anticipatory, simultaneous, and posterior counterattacks) according to round and compare winning and nonwinning competitors in university taekwondo competitors. The results support those of studies conducted in other competitive contexts, and reveal the frequency of taekwondo athletes' tactics and changes in the use of these tactics between rounds (2,4,15,19,34,35). Specifically, the results showed more frequent use of direct attacks in the third round than in the first, more anticipatory counterattacks in the third round than in the second, and more in the second round than in the first. This could be because competitors tend to use the first round to evaluate opponents and conserve their energy for the third round (2). The rhythm of the bout increases in the third round because this round is decisive to win the match; winners attempt to finish the bout rapidly and nonwinners attempt to take the lead (34).
The results of the current examination in relation to match outcomes show that tactical behavior is similar between the 2 groups of competitors (winners and nonwinners), except with respect to indirect and anticipatory actions. In contrast to other studies (4,29), which find few differences between winners and nonwinners, our results indicate that winners perform fewer indirect and more anticipatory actions than nonwinners do. Similar results were reported by other researchers (25,36), who found that less-skilled athletes tended to initiate attacks, because less-experienced athletes performed more aggressive and less-controlled kicks (21). Moreover, it seems that less-skilled athletes are less powerful over greater distances (10), which may force them to take a step, feint an attack, or move closer to their opponent in an attempt to reduce the distance from their opponents before kicking, which makes the attack indirect. On the contrary, attacks seem easier to execute than counterattacks, which require anticipation of an attack (25,36). Judging the right instant to act requires experience, for example, in perceptions of head and chest movements (17,32,38). In addition, higher-level athletes respond faster than lower ranked counterparts do (31,38). This may explain why winners perform more anticipatory counterattacks than nonwinners do.
Another objective of this study was to analyze the interaction effect of tactics according to match outcome (winning and nonwinning) in each round of a bout (first, second, and third). In contrast with the results of previous studies (4), which found no differences between winning and losing athletes in the actions performed over the rounds, the results of this study indicate differences between groups, especially toward the end of a bout. On the one hand, these results indicate that winners and nonwinners behave similarly in the first 2 rounds except in anticipatory and simultaneous counterattacks, where winners perform more anticipatory actions in the second round than nonwinners do, who perform more simultaneous actions at the first round than winners do. However, more differences appear between groups in the third round. Winners perform more anticipatory, simultaneous, and posterior counterattacks than nonwinners do, who perform more direct and indirect attacks. According to other studies (21), being more aggressive in bouts distinguishes less-experienced competitors. It appears that lower level competitors tend to attack because counterattacking is more complex to perform (25), that is, it requires anticipation and proper reaction to an opponent's behavior (i.e., steps, changes of stance or direction, feints, footwork, and shifts) (36). Thus, counterattacking may be decisive for athletes who win.
This difference between winners and nonwinners is evident from their behavior throughout the bout. Winners perform more anticipatory actions in the second and third rounds than in the first round and more simultaneous actions in the third round than in the first. They perform fewer indirect actions in the third round than in the second round. Otherwise, nonwinners perform more direct actions as they progress through a bout (more in the second and third rounds than in the first and more in the third round than in the second) and more indirect actions in the second and third rounds than in the first round. These results show that the characteristic behavior of each group (direct and indirect attacking actions by the nonwinners and anticipatory, simultaneous, and posterior counterattacking actions by the winners) is more obvious when they seek to improve their scores toward the end of a bout. Previous studies (5) recommend that competitors choose the most suitable techniques to surprise their opponents and counter their tactics, which could explain why less-experienced competitors opt to attack, and consequently experienced competitors counterattack to prevent their opponents from scoring.
Because the aim of this study was to analyze the tactical behavior of competitors, it did not focus on analyzing the scores for each action (effectiveness). Future studies should examine the effectiveness to discover which actions score and when these appear in a bout. On the contrary, the use of systematic observation methods may encourage improvement in taekwondo, because such methods would allow taekwondo coaches to turn their attention to the success of young athletes and those in elite categories. Moreover, it must be noted that the sample for this study was drawn from university competitors, so the results should be generalized only to the university level. Further investigations are necessary to confirm the permanence of these trends and identify changes because this is the first study that analyzes these variables in this population. Moreover, some of these university athletes are international competitors, which could allow future studies to ascertain whether elite athletes vary their tactics according to type of tournament and the skill level of their opponents. Despite the above limitations, these data may provide a better understanding of the tactical behavior of taekwondo athletes, and define and classify actions in a competitive situation.
The use of an observational tool allows coaches to recognize the preferred actions of athletes in competitive situations during training with the aim of improving their performance. This study suggests that tactics of winners and nonwinners change over the course of a bout, with more direct attacks by nonwinners and greater reliance on anticipatory actions by winners. Taekwondo requires a variety of skills and diversification of techniques, and the physical flexibility to react appropriately and in a timely manner to the opponent's actions (36). Coaches should consider this characteristic behavior (impulsivity and incaution for nonwinners and composure for winners), and the increased rate of activity at the end of a bout, and adapt their tactical and power training accordingly. That is, it is suggested that training sequences include powerful attacks and counterattacks that familiarize the athletes with situations in which they must score and defend themselves against an opponent's counterattacks.
On the contrary, the present findings regarding match outcome indicate differences in tactical behavior between winners and nonwinners. Nonwinners appear to be characterized by less-controlled and less-powerful attacks. They perform more indirect attacks than winners do, who apparently recognize the right instant to counterattack and score. As a bout progresses, it seems that the key point for better performance is powerful, faster, and controlled counterattacks, because counterattacking actions may allow athletes to avoid an attack and counterattack with a powerful kick (i.e., anticipatory, simultaneous, and posterior counterattack) to score. Further, the results suggest that coaches and athletes should conduct tactical training for a variety of counterattacks, especially simulating these actions at the end of a bout. Thus, practice bouts for less-skilled competitors should include actions that require quick reactions and significant generation of power. Moreover, it is suggested that coaches train lower level athletes to be confident in their tactics and counterattack, particularly in the third round.
The authors would like to express their gratitude to the Spanish Taekwondo Federation for providing the videos for this study. This research was supported by a grant from the Catholic University of Valencia (2013-158-001).
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