Andrzej Kędra's research while affiliated with Gdansk University of Physical Education and Sport and other places

Background: There is a consensus among combat sports researchers regarding the important role of evaluating the comprehensive special fitness and performance of athletes. This is due to the specific structure of tasks performed in these sports as they require a comprehensive and integrated function of broadly understood physical fitness. The present study aimed to develop and check the Special Brazilian Jiu-Jitsu Fitness Test: Takedown Zone (SBJJFT-TZ), Gi formula’s reliability. The major task of this sport-specific tool is to illustrate the comprehensive special fitness and performance of professional Brazilian jiu-jitsu athletes. Methods: The study covered 27 BJJ athletes (age in years: 25.36 ± 2.99; height: 175.04 ± 5.70 cm; weight: 76.56 ± 8.59 kg; BMI: 24.96 ± 2.30; 6.33 ± 2.51 years of training) with a high sports skill level. A coaches’ ranking of the athletes studied according to sports achievement was developed. An experimental approach to the problem was employed, with the SBJJFT-TZ assessment, including throws and specialized locomotion, performed on two dates (seven days apart). The test parameters were recorded and, using a specialized formula, an index showing comprehensive special fitness was calculated. To verify the test’s validity and reliability, using statistical procedures, the results were comparatively analyzed (Student’s t-test for the dependent variables), and the relationships between rankings were examined (Pearson’s r linear correlation). The level of statistical significance was set at p < 0.05. Results: The analyses showed statistically significant relationships with very high strength between coach ranking and SBJJFT-TZ parameters for both dates (R = 0.73–0.88; p < 0.001). A similar trend of significant correlations was noted between the first and second SBJJFT-TZ dates (R = 0.96–0.98; p < 0.001), and the strength of the coexistence was almost complete. The test-retest procedure for SBJJFT-TZ showed similar levels for the parameters studied, without significant variation (p > 0.05) but with a weak effect profile (d = 0.03–0.06). Internal variation in the variables was very low (HR CV < 10%) and moderate (Throws and Index CV = 20.82–32.25%). Significantly different throwing performance between sets was shown, with an advantage in the first round of work compared to the second, and a moderate effect (p < 0.05; d = 0.38–0.39). Conclusions: The identification of relationships, the comparison, and the test-retest procedure showed the high application value of SBJJFT-TZ. The proposed tool provides a reliable cross-sectional evaluation of BJJ athletes’ special fitness and performance in the stand-up fighting plane, as well as at the moment of achieving an advantage over the opponent, and favors implementation in field conditions.

Background: Sportive ju-jitsu in the fighting format is characterized by high intensity and complexity in terms of the fighting system. Athletes must engage in versatile combat involving actions on different planes, under varying conditions of contact and distance. The aim of this study was to assess and analyze the level of physical fitness in ju-jitsu athletes and its relationship with technical-tactical training. Methods: Ten athletes were subjected to the study, evaluating agility, speed, strength, and endurance. The level of technical-tactical preparedness was also assessed based on recordings of matches in three parts of the fight, calculating the effectiveness, activity, and efficiency of attacks. Results: Agility, striking speed, and retreat were positively correlated with effectiveness in the third part of the fight and overall average effectiveness. On the other hand, flexibility and ground mobility showed a negative correlation with fight effectiveness. Conclusions: A significant relationship was demonstrated between physical fitness and indicators of technical-tactical preparedness. Practical implications involve guidance for coaches in implementing training focused on specific areas of physical fitness that impact the level of technical-tactical training.

Background: The observation and specialized analysis of confrontations in combat sports are fundamental for making corrections in training programs as well as for modifying individual technical–tactical profiles of athletes in such activities. These actions comprehensively assess the course of sports activities and ultimately inspire and guide the type of training in academies and sports clubs. The aim of the study was a general and detailed analysis of sport fighting in JU-JITSU during a top-tier tournament, in the fighting formula for the entire competition and for each weight category. Methods: The research material consisted of multimedia recordings of sports fights taken during the World JU-JITSU Championships in the fighting formula, Wroclaw 2016. A total of 229 tournament fights were analyzed in seven weight categories. For the purpose of evaluating the structure of the fight, a retrospective analysis of the recorded empirical material was conducted, and technical–tactical preparation (TTII) indicators were calculated, both in a global tournament context and for individual weight categories. Results: Of the 229 matches, more than half were decided by the advantage of technical points (58.52%) within the regulatory fight time, while in 74 clashes, victory was declared by Full Ippon (32.31%) before the designated fight time. Activity and attack effectiveness, as well as the number of technical points, were highest in the first part of the fight. Significant variations were observed in terms of activity, attack effectiveness, and point gains for all parts of the clash, and for effectiveness in the weight categories compared to the second part. The most frequently occurring penalty was the minor shido penalty, while the offense was the lack of fighting in the second part of the duel. The total fight time was 256 s, of which 144 s were effective fighting, and 112 s were breaks. Conclusions: The analysis of sports fight observations revealed that the majority of fights ended with a technical point advantage win (58.52%), with notable activity and attack effectiveness in part I. Middleweight fighters were most active early on, while heavyweight categories dominated later phases. Attack efficiency varied across weight categories. Penalties were predominantly minor (shido), and the total fight time included 144 s of effective fighting and 112 s of breaks.

Background and Study Aim: Breaking rules in combat sports can finally result in getting lower score that has an impact on the outcome of a bout. Currently there are no papers dealing with demerits in kickboxing. The objective of the paper was knowledge about demerits of the regulations occurred during amateur kickboxing bouts in K1 formula. Material and Methods: Thirty one bouts were videotaped and 31 kickboxers were evaluated. Based on computed indicators (activeness, efficiency and effectiveness of the attack) the relation between the number of demerits and the indicators of technical and tactical training was searched. Results: The most common demerit was forbidden holds of the rival (it concerned 13 (41.9%) competitors and it was 31.7% of all demerits). Competitors made on average 1.32 demerits. The effectiveness of the attack was on average 46.63 points, activeness of the attack was on average 91.61 points, efficiency of the attack was on average 60.16 points. Conclusions: The largest group of competitors had 2 demerits in a bout. The largest number of demerits in a bout was 3. Forbidden holding was the most common demerit of kickboxers in K1 formula. Effectiveness, activeness and efficiency of the attack were on a high level and were not connected to the number of demerits in a bout.

Background and Study Aim: Ratio of fights won is important to kickboxers on professional and amateur levels. Knockout is the most economical way of winning the fight. The objective of the paper is the effectiveness of kickboxing techniques and their impact on winning the fight by knockout. Material and Methods: There were 156 participants in the study (61 amateurs and 95 professionals). Their total number of fights won by knockout was 188 and the amateur competitions they participated in complied with the K-1 ruleset. Fighters were 19 to 32 years old and their training experience was on the average 7.36 yrs. ±3.24 yrs. The shortest training lasted 3 yrs. and the longest one 18 yrs. The study was conducted using the analysis of videos of professional fights as well as diagnostic survey conducted in a group of amateur fighters. The survey included questions about training experience and techniques used in a fight won by knockout. The video analysis also included the techniques used in a fight won by knockout. Results: Hook high and roundhouse kick high were the most effective kickboxing techniques in winning fights by knockout. The comparison of techniques used in a knockout between amateur and professional fighters did not bring any statistically significant differences. It was shown however that professional fighters used the most effective techniques: more often than amateurs. Conclusions: During the training the fighters should pay special attention to constructing combinations of punches and kicks using hook high and roundhouse kick high techniques. Using proper techniques as well as numerous repetitions of the most effective techniques should be a part of any training of a kickboxing fighter.

Aim. Ju-jitsu athletes are expected to reach competitive readiness adequate for the demands of tournaments. Apart from technical expertise, one of the aspects of readiness is general and special preparation. This is critical to the athlete’s level of achievement since it helps him or her cope with the training load as it is linked to mental preparation and ensures that the athlete uses technical and tactical variants more accurately during a fight. The cognitive aim of this study is to characterize fitness preparation of top athletes from the Polish Ju-jitsu Association. The practical aim is to identify talented athletes who can become members of national teams participating in international tournaments. Basic procedures. The study evaluated 29 national Ju-jitsu team members in the preparation period (pre-competition mesocycle), who expressed their interest and consent to participate in the experiment. 13 of these athletes were listed in the Ju-jitsu International Federation ranking, including 3 medalists in the World Championship in Wrocław, Poland (2016). 13 tests of general physical fitness were performed by means of selected tests from the Eurofit test battery, the ICSPFT tests and additional strength tests. 8 special physical fitness tests were also used. The results were described using cluster analysis and comparison of fitness profiles. Results and main findings. The differences between three clusters in general physical fitness were noticeable in the performance of pull-ups (1<2 and 2>3 clusters), the Cooper test ( 1<2 and 1>3 clusters), the shuttle-run test (1>2 and 2<3 clus-ters), the sit-and-reach test (2<3, 2<1 clusters), maximal hand-grip-strength test (1>3 cluster), the Flamingo balance test (1-3 and 2-3 clusters). In the special physical fitness tests, pronounced differences were observed in performance of speed punches (1>2 cluster), 1/Flexibility Index (1>3 cluster), evasive actions (1<3, 2<3 clusters) and push-ups (1>2 and 1>3 clusters). The profiles of 3 of the clusters were highly dissimilar. Conclusions. The studied athletes were characterized by high differences in fitness-related readiness level. Their profiles in 3 clusters show that some athletes in the national level group match top athletes at the international competitive level in these terms. Analysis of individual profiles allows for effective diagnosis and classification while revealing strengths and weaknesses in the fitness preparation of Ju-jitsu athletes. Therefore, it should be used for testing and monitoring modifications over the training cycles. Knowledge of the structure and the data on baseline physical fitness and special fitness in elite athletes may be useful for the development of individual training programmes for Ju-jitsu athletes.

Background & Study Aim: Contemporarily, a phenomenon of the increasing number of women who participate in combat sports has been observed. Te aim of this study was to obtain knowledge about body build and body composition and profile of special fitness in women who practice ju-jitsu. This knowledge can be used in monitoring of the status of physical preparation and effects of training in female athletes who represent a variety of weight and age categories. Material & Methods: Te participants of the study were 12 female members of the national ju-jitsu team, aged 19.5± 3.23, repre-senting two weight categories: the lighter category up to 55 kg (n=6, 51.72± 4.76 kg) and the heavier category (n=6, 65.67 ±3.88 kg). Body height was measured using an anthropometer. Body mass was measured using a weight scale. Te evaluation of body composition was performed under standard conditions according to the bioelectric impedance analysis guidelines. Estimated were the body mass (index BMI) and body composition (FFMI and FMI) parameters. Fitness was assessed by means of a battery of tests used in karate (SPFT) and a judo special fitness test (SJFT). Maximal static strength in the dominant hand (HGS) was measured using a handgrip dynamometer. A Polar 810i heart rate monitor was used. Basic descriptive statistics were calculated. Te significance threshold for differences between mean values was p<0.05. Results: A very strong correlation between FMI and FFMI (r=0.98, p<0.001) was observed. Te averages for the lighter group were significantly lower than for the heavier group as per BMI, FFMI, FMI (p<0.001) and fat percentage in total mass (p=0.005). During fitness evaluation, no statistically significant differences were found between the heavier and lighter weight categories in terms of SPFT, HGS and SJFT (p>0.05). Te differences between mean values of anthropometric measurements and parameters were not significant for age categories (p>0.05). Significant differences were found between the mean values for age categories in the quality of push-ups, segment C of the SJFT, and in total throws. Te SJFT index in the older group was better (i.e., lower) than in the younger group. Conclusions: Te body composition of female ju-jitsu athletes is associated with their weight category, but does not affect performance in special fitness tests. Te results of tests on rapid kicks, push-ups and special endurance in the SJFT (total throws and index) are dependent on the age factor. Profile analysis enables group and individual diagnosis of fitness preparation. Such diagnosis can be used for the comparison of contestants at the time of measurement, as well as in the process of monitoring changes occurring in a training cycle. Te established structure of special fitness among female top ju-jitsu contestants can be used for comparisons with male representatives.