Physiological Responses and Time-Motion Analysis of Kickboxing: Differences Between Full Contact, Light Contact, and Point Fighting Contests

Time-Motion and Technical-Tactical Aspects of Glory World Series Matches in the Male Middle-Heavy-Weight Category

PURPOSE

To characterize the time structure of K1 kickboxing matches of Glory World Series (Glory) and to determine potential differences between winners and losers.

METHODS

Seventeen matches of Glory 2019 (17 first rounds, 13 second rounds, and 8 third rounds) were video-analyzed to quantify (1) the time expended in high- and low-intensity activity and pauses, (2) the number and pattern of attacks, and (3) the number of effective attacks. Fighters were professional male athletes (age 27.9 [2.7] y) of the middle-weight category (85 kg). The number and the pattern of attacks and the number of effective attacks were compared between winners and losers.

RESULTS

The mean times expended in high- and low-intensity activity and pauses were 234.6 (133.9) seconds, 97.4 (60.1) seconds, and 36.0 (19.9) seconds, respectively, resulting in an effort-to-pause ratio of ∼1.8:1. Compared with losers, winners presented (1) a greater number of attacks in the second round (P = .004) and entire match (P = .009), (2) a greater number of attacks containing 3 attacks in sequence in the second round (P = .001) and attacks containing >3 attacks in the third round (P = .049), and (3) a greater number of effective attacks in the second round (P = .011) and entire match (P = .008).

CONCLUSIONS

The findings of the present study indicate that K1 kickboxing in Glory matches presents a ∼1.8:1 effort-to-pause ratio and that winners perform more attacks, effective attacks, and attacks in sequence. These data provide useful insights to improve the training specificity of kickboxing athletes.

Mathematical simulation of damage detection for fighting athletes and equipment based on conjugated polymer development

Traditional combat sports equipment usually uses synthetic materials, such as polyurethane and synthetic leather. Although these materials have a certain degree of strength and durability, they have poor flexibility and antibacterial properties, making it difficult to provide stable support and protection for athletes. In order to enhance the antibacterial properties and flexibility of sports equipment and reduce the risk of injuries to athletes, this article conducts in-depth research on the development of combat sports equipment using conjugated polymers. This article first selects polypropylene (PP) as the base material for sports equipment for combat athletes, and uses the gas phase polymerization method to prepare the material; then uses chitosan as an antimicrobial agent and uses the oxidative degradation method to prepare it; after that, this article coats the chitosan antibacterial agent on the prepared PP material, and uses a combination of dipping and calendering for antibacterial treatment; finally, this article uses the spunbond melt-blown composite method to fill and combine the top equipment of combat athletes to achieve the structural design of sports equipment. In order to verify the effectiveness of the equipment, this article conducted equipment performance testing and sports injury simulation. The results showed that the average diameter of the antibacterial zone of this sports equipment reached more than 1 mm, and in the injury risk test, the risk of athletes' joint and muscle injuries was reduced by 16.9% and 20.5% respectively. Research shows that developing combat sports equipment based on conjugated polymers can help reduce the risk of injury to athletes and improve the safety of combat sports.

Comparison of Head Strike Incidence under K1 Rules of Kickboxing with and without Helmet Protection-A Pilot Study

BACKGROUND

Kickboxing is a combat sport that encompasses various forms of competition. K1 kickboxing is conducted without any restrictions on the force of strikes, and the bout can end prematurely through a knockout. Headgear has been introduced in amateur kickboxing to safeguard the head. However, scientific studies have shown that despite their use, serious head injuries can still occur. The aim of this study was to evaluate the temporal structure of the bout by calculating the number of head strikes in K1 kickboxing bouts with and without headgear.

METHODS

Thirty K1 kickboxing bouts were analyzed, with 30 participants included in the study. The fights were conducted according to the World Association Kickboxing Organization (WAKO) rules. The bouts consisted of three rounds of 2 min each, with a 1 min break between rounds. Sparring pairs were arranged according to weight categories. The first bouts were conducted without headgear, and two weeks later, the fights were repeated with WAKO-approved headgear. The number of head strikes was assessed retrospectively by analyzing video recordings of the bouts, categorizing strikes as hand or foot strikes, and differentiating between strikes that hit the head directly or indirectly.

RESULTS

The results showed statistically significant differences between bouts with and without headgear in terms of the number of strikes to the head (p = 0.002), strikes directly to the head (p < 0.001), all hand strikes to the head (p = 0.001), hand strikes directly to the head (p = 0.003), and foot strikes directly to the head (p = 0.03). Higher values were observed in bouts with headgear.

CONCLUSIONS

Headgear increases the probability of direct strikes to the head. Therefore, it is important to familiarize kickboxers with the use of headgear in their sport to minimize head injuries.

Energy System Contributions during Olympic Combat Sports: A Narrative Review

This narrative review focuses on the studies that estimate the energy systems' contributions during match simulations of striking (boxing, karate, and taekwondo), grappling (judo), and weapon-based (fencing) Olympic combat sports. The purpose is to provide insights into the metabolism of these athletes. In striking Olympic combat sports, the oxidative contribution varied from 62% (in karate and taekwondo) to 86% (in boxing), the ATP-PCr system contribution varied from 10% (in boxing) to 31% (in taekwondo), and the glycolytic contribution was between 3% (in the third round of taekwondo) and 21% (in karate). In grappling combat sports, only judo was studied, and for a 4 min match, the oxidative contribution was 79%, followed by 14% ATP-PCr system contribution and 7% contribution from the glycolytic system. In fencing, the only weapon-based Olympic combat sport, the oxidative contribution varied from 81% (in the first bout) to 90% (in the second bout), followed by 9% (bout 2) to 12% (bout 1) contribution from the ATP-PCr system, and 0.6% to 7% contribution from the glycolytic system during 3 × 3 min bouts of épée match simulation. Hence, Olympic combat sports are primarily powered by the oxidative system, but the key scoring actions are likely fueled by anaerobic pathways.

Effect of CrossFit Training on Physical Fitness of Kickboxers

Background: Kickboxing is a combat sport that is complex in technique, tactics, and movement structure, and requires an adequate level of motor skills as a foundation for activities during competitions. General physical fitness, defined as the effect of the externalization of motor skills, is the basis for athletic training regardless of the sport. The aim of this study was to determine the effect of modified training based on the principles of CrossFit on the development of general physical fitness in a group of kickboxers compared to a control group. Methods: The study was experimental in nature and was conducted in a group of 60 kickboxers, divided into experimental and control groups. Participants were selected by purposive sampling, and the criteria were training experience, sports skill level (minimum class 1 athletes), and consent to participate in the experiment. The intervention in the study group involved the introduction of CrossFit-based training into a conventional kickboxing training program. General and special physical fitness of the athletes were diagnosed. Results: Statistically significant differences were found in general fitness in terms of abdominal strength (p < 0.001), pull-ups (p < 0.001), dynamometric measurement of handgrip force (p < 0.001) (kg), clap push-ups (p < 0.001), standing long jump (p < 0.001), shuttle run (p < 0.001), sit-and-reach (p < 0.001), and tapping (p < 0.001). Furthermore, changes in special fitness were also demonstrated for the special kickboxing fitness test (SKFT) (p < 0.02), the total number of punches (p < 0.001), punching speed (p < 0.001), and hip turning speed (p < 0.001). There was also a correlation between characteristics of general fitness and special fitness (p < 0.001). Conclusions: The experimental training program based on the principles of CrossFit training had a positive effect on the general and special kickboxing physical fitness.

Technical-tactical analysis of small combat games in male kickboxers: effects of varied number of opponents and area size

Background

To handle the competition demands, sparring drills are used for specific technical–tactical training as well as physical–physiological conditioning in combat sports. While the effects of different area sizes and number of within-round sparring partners on physiological and perceptive responses in combats sports were examined in previous studies, technical and tactical aspects were not investigated. This study investigated the effect of different within-round sparring partners number (i.e., at a time; 1 vs. 1, 1 vs. 2, and 1 vs. 4) and area sizes (2 m × 2 m, 4 m × 4 m, and 6 m × 6 m) variation on the technical–tactical aspects of small combat games in kickboxing.

Method

Twenty male kickboxers (mean ± standard deviation, age: 20.3 ± 0.9 years), regularly competing in regional and national events randomly performed nine different kickboxing combats, lasting 2 min each. All combats were video recorded and analyzed using the software Dartfish.

Results

Results showed that the total number of punches was significantly higher in 1 versus 4 compared with 1 versus 1 (p = 0.011, d = 0.83). Further, the total number of kicks was significantly higher in 1 versus 4 compared with 1 versus 1 and 1 versus 2 (p < 0.001; d = 0.99 and d = 0.83, respectively). Moreover, the total number of kick combinations was significantly higher in 1 versus 4 compared with 1 versus 1 and 1 versus 2 (p < 0.001; d = 1.05 and d = 0.95, respectively). The same outcome was significantly lower in 2 m × 2 m compared with 4 m × 4 m and 6 m × 6 m areas (p = 0.010 and d = − 0.45; p < 0.001 and d = − 0.6, respectively). The number of block-and-parry was significantly higher in 1 versus 4 compared with 1 versus 1 (p < 0.001, d = 1.45) and 1 versus 2 (p = 0.046, d = 0.61) and in 2 m × 2 m compared with 4 m × 4 m and 6 × 6 m areas (p < 0.001; d = 0.47 and d = 0.66, respectively). Backwards lean actions occurred more often in 2 m × 2 m compared with 4 m × 4 m (p = 0.009, d = 0.53) and 6 m × 6 m (p = 0.003, d = 0.60). However, the number of foot defenses was significantly lower in 2 m × 2 m compared with 6 m × 6 m (p < 0.001, d = 1.04) and 4 m × 4 m (p = 0.004, d = 0.63). Additionally, the number of clinches was significantly higher in 1 versus 1 compared with 1 versus 2 (p = 0.002, d = 0.7) and 1 versus 4 (p = 0.034, d = 0.45).

Conclusions

This study provides practical insights into how to manipulate within-round sparring partners' number and/or area size to train specific kickboxing technical–tactical fundamentals.

Trial registration

This study does not report results related to health care interventions using human participants and therefore it was not prospectively registered.

Evaluation of the Level of Technical and Tactical Skills and Its Relationships with Aerobic Capacity and Special Fitness in Elite Ju-Jitsu Athletes

Background: Ju-jitsu training has to be comprehensive in terms of training intensity, developing a wide range of physical fitness and learning multiple technical skills. These requirements result from the specificity of the competition characteristic of the sport form of this martial art. The aim of this study was to evaluate the aerobic capacity and special physical fitness of ju-jitsu athletes at the highest sports performance level and to determine the relationships between special fitness and the indices of technical and tactical skills. Methods: In order to determine the current level of special fitness of the athletes, a set of karate fitness tests were used, namely, the Special Judo Fitness Test and the Kickboxer Special Physical Fitness Test. Furthermore, maximal oxygen uptake (VO₂peak) was measured using a graded exercise test in a group of 30 sport ju-jitsu athletes at the highest level of sports performance. To evaluate the level of technical and tactical skills, an analysis of recordings of tournament bouts was carried out, and, based on the observations, the indices of effectiveness, efficiency, and activeness of the attack were calculated. Results: Individuals with higher fitness were more active and effective in the attack. The special efficiency indices showed significant correlations with the technical and tactical parameters. Better fighting performance was dependent on the speed of the punches, kicking range, and the results of the special fitness tests. Conclusions: To achieve greater efficiency and effectiveness of sport ju-jitsu, the training process should be based on comprehensive motor development and an optimal level of special fitness.

Evaluation of the Body Composition and Selected Physiological Variables of the Skin Surface Depending on Technical and Tactical Skills of Kickboxing Athletes in K1 Style

BACKGROUND

Kickboxing is a combat sport with high demands on fitness and coordination skills. Scientific research shows that kickboxing fights induce substantial physiological stress. Therefore, it is important to determine the body composition of athletes before competitions and to analyze the skin temperature and skin pH during the fight.

METHODS

This study aimed to determine the body composition, skin temperature, and skin pH in kickboxers during a fight according to K1 rules. A total of 24 kickboxers (age range: 19 to 28 years) competing in a local K1 kickboxing league participated in the present study.

RESULTS

Changes in skin temperature and pH were observed and significant correlations were found between body composition and weight category.

CONCLUSIONS

Changes in skin temperature and pH were demonstrated after each round of the bout. Level of body fat and muscle tissue significantly correlates with technical-tactical skills of the K1 athletes studied.

Physiological Responses and Bout Analysis in Elite Kickboxers During International K1 Competitions

Background: Kickboxing is a combat sport with various forms of competition. Kickboxing according to the K1 rules is one of the most interesting and quickly developing forms of kickboxing. According to the K1 rules, it is possible to use a variety of techniques with great force. The aim of this study was to investigate the physiological responses during a real sports fight and to perform a technical and tactical analysis of the kickboxing bout according to the K1 rules. Methods: This study was conducted during two cycles of the international kickboxing league according to the K1 rules in a group of 15 elite athletes. The indicators of technical and tactical training were evaluated in real sports bout. Blood lactate (LA) levels and heart rate (HR) were measured during and after the bout. Results: The efficiency of the attack was on average 59.3 ± 2.7, its effectiveness was 50.3 ± 10.01, and its activeness was 112.3 ± 29. The peak LA concentration was 14.6 ± 1.9 mmol/L. LA concentration did not decrease to baseline after 20 min of recovery. Conclusion: A kickboxing bout was found to induce strong physiological stress for the participants. Reported HR and LA concentration show that the intensity of the fight was close to maximal, and anaerobic metabolism played an important role during a fight.