Katarzyna Sterkowicz-Przybycień

Techniques frequently used during London Olympic judo tournaments: A biomechanical approach

Feedback between training and competition should be considered in athletic training.The aim of the study was contemporary coaching tendencies in women s and men s judo with particular focus on a biomechanical classification of throws and grappling actions. Throwing technique frequencies grouped in the seven biomechanical classes were dependent on gender. A significant difference was found between frequencies of variable arm of physical lever technique scored by males and females as compared to the techniques counts. Significant differences between men who competed in extra lightweight and heavy weight concerned the frequency of the techniques used with maximum arm or variable arm of physical lever and a couple of forces applied by trunk and legs.In females a tendency to higher frequency of techniques that used couple of forces applied by arm or arms and leg was observed in extra lightweight compared to the heavy weight. Because the technique preferred in the fight depends on a gender and weight category of a judoka, the relationships found in this study, which can be justified by the biomechanics of throws, should be taken into consideration in technical and tactical coaching of the contestants. A method used in this study can be recommended for future research concerning coaching tendencies

Establishing Normative Data for the Special Judo Fitness Test in Female Athletes Using Systematic Review and Meta-Analysis

Abstract Sterkowicz-Przybycień, KL and Fukuda, DH. Establishing normative data for the special judo fitness test in female athletes using systematic review and meta-analysis. J Strength Cond Res 28(12): 3585–3593, 2014—Conflicting results have been documented in the Special Judo Fitness Test (SJFT) for mean parameters of performance between male and female judo athletes matched by age and competitive level. Therefore, it is debatable whether previously established norms for the SJFT prepared for men, should be adopted for use in women. The goal of this investigation was to prepare standards to allow coaches and researchers to control and evaluate training effects in female judoka. Systematic review was used to compile previously published scientific studies containing information on female judo athletes who were tested using the SJFT. The results were derived using meta-analysis and included data obtained from 11 relevant studies published between January 1997 and December 2013. Combined mean and SDs were computed based on studies containing 161 individual results from the SJFT. A 5° scale was adopted as follows: Excellent = highest 5%, Good = next highest 15%, Regular = middle 60%, Poor = next lowest 15%, and Very poor = lowest 5%. The results of the current investigation provide normative data for the SJFT for junior and senior female judoka. Classification for each of the parameters of the SJFT, including number of throws completed during the test, heart rate (HR) measured immediately after the effort, HR after a 1-minute recovery period and SJFT index, were established. This normative data can be used in the design of training programs for female judoka, as well as evaluation after training, and in preparation for competition.

Anthropometrical Profile of Judo Athletes: Comparative Analysis Between Weight Categories

Este estudio comparo las caracteristicas antropometricas de atletas de judo de diferentes categoriasde peso. La muestra estuvo compuesta por 104 judocas hombres brasilenos de nivel nacional/internacional de las siete categorias oficiales de peso: superligero (-60 kg; n = 16), semiligero (-66 kg; n= 12), ligero (-73 kg; n= 24), semimedio (-81 kg; n= 25), medio (-90 kg; n= 15), semipesado (-100 kg; n= 7) y pesado (+100 kg; n= 5). Se tomaron lassiguientesmedidasantropometricas: masa corporal, estatura, pliegues cutaneos (triceps, subescapular, suprailiaco, abdominal, muslo frontal y pierna medial), circunferencias (pecho, brazo relajado, brazo contraido, antebrazo, muneca, muslo proximal, pantorrilla y tobillo) y diametros oseos (humero y femur, biacromial, pecho, profundidad del pecho y biliocristal). El somatotipo de los grupos de las siete categorias de peso secalculo mediante el metodo de tres dimensiones. Se utilizo unanalisis unidireccional de varianza y la prueba de Tukey para comparar los gruposen aquellos datos distribuidos normalmente, mientras quese utilizo la prueba de Kruskal-Wallis en aquellos datos que no siguieron una distribucion normal (P<0,05). Los principales resultados obtenidos fueron: (1) la altura diferia en las categorias de pesono consecutivas, excepto entre las categorias de -60 kg y -66 kg; (2) los pliegues cutâneos de las cuatro categorias mas ligeras no difirieron entre ellos, y el grupo de +100 kg presento los valores mas altos en comparacion conlas demas categorias de peso; (3) en la mayoria de circunferencias, los grupos de -60 kg y -66 kg presentaronvalores mas bajos en comparacion con las tres categorias de mayor peso (-90 kg, -100 kg and +100 kg); (4) las categorias de somatotipo fueron similares en los tres grupos mas ligeros (-60 kg, -66 kg,-73 kg), mientras que la categoria mas pesada difirio del resto de grupos; (5) la mayor parte de las diferencias entre los grupos se localizaron en los diametros oseos. En conclusion, las principales diferencias entre las categorias de pesofueron los diametros oseos y las circunferencias, mientras que la altura y espesor de los pliegues cutaneos variaron principalmente entre las categorias mas ligeras y pesadas.

Sex and Weight Category Differences in Time-Motion Analysis of Elite Judo Athletes: Implications for Assessment and Training

Abstract Sterkowicz-Przybycień, K, Miarka, B, and Fukuda, DH. Sex and weight category differences in time-motion analysis of elite judo athletes: implications for assessment and training. J Strength Cond Res 31(3): 817–825, 2017—The purpose of this investigation was to support training program development through the comparison of combat and pause phases during elite male and female judo competition in athletes of varying weight categories. A total of 1,411 video recorded judo matches between athletes who qualified for the 2012 Olympic Games were analyzed. Within the matches, 111,203 competitive situations were categorized as combat (with subphases of approach, gripping, attack, defense, and groundwork) or pause phases. Time-motion analysis data were compared between extra light, light, middle, and heavyweight categories for men and women. Median times varied between sex and weight category groups for individual combat (23.9–28.5 seconds), pause (4.0–8.8 seconds), and combat subphases (p ⩽ 0.05). Sex-based differences in accumulated combat and combat subphase times were primarily found in the middleweight athletes. Heavyweight female athletes had longer accumulated groundwork and pause times, extra lightweight women had greater groundwork time, and both extra light and lightweight women had shorter accumulated attack times compared with their male counterparts. No differences between men and women were found for the time to complete an individual combat action; however, the pause phase and most of the combat subphases displayed differences. The lightest and heaviest judo athletes displayed unique characteristics compared with athletes in the other weight categories, particularly in the attack, defense, groundwork, and pause phases. These results have important implications related to training program design and support the need for the development of normative data for male and female judo athletes of varying weight categories.

The effects of training and creatine malate supplementation during preparation period on physical capacity and special fitness in judo contestants

The purpose of the study was to determine the effect of 6-weeks training and creatine malate supplementation demonstrated in anaerobic capacity and aerobic power and in special judo fitness test performance (Throws in Total and Index in SJFT).

Sexual dimorphism in anthropometric and fitness measurements of top ju-jitsu contestants

A ju-jitsu fight is characterized by a great variety of complex technical and tactical actions which can be used by both men and women in vertical and horizontal positions. Division into weight categories helps provide equal chances for the competitors, not only in terms of body weight but also their locomotor abilities, range of punches and kicks (used in the first phase of the fight), strength and leverage after catching the clothes to perform a throw (the second phase of the fight) and using immobilization, choke and joint manipulation techniques during groundwork (in the third phase of the fight). A popular tendency before tournaments is body mass reduction that affects body composition. The athletes usually aim at increasing the percentage of fat-free mass in overall body mass in order to improve relative strength when competing in a particular weight category [1]. The fight is characterized by increased activity in both attack and defence, which represent a high-intensity exercise. Duration of these intermittent efforts largely depends on the effectiveness of technical and tactical actions in individual phases of the fight. Fighting according to the regulations for sport ju-jitsu is a combination of the skills typical of karate and judo competition [2,3]. Therefore, it was adopted that special fitness tests developed for karate (SPFT) and judo (SJFT), although having its individual specificity, might be used in ju-jitsu [4]. Conception of study. It was assumed that a sport ju-jitsu fight makes similar demands on both women and men [5]. Division into weight categories in both genders provides equal chances for all the competitors. We propose a hypothesis that women differ more in body build and composition than men rather than in quality of performing specific fitness tests which contain technical skills typical of the judo fight. The aim of this study is to compare anthropometric data, body composition and sport-specific fitness of male and fe male subjects, and to establish an anthropometric profile and fitness patterns of elite ju-jitsu athletes.

Stress in sport situations experienced by people who practice karate

Background Sport situations can be difficult. Stress can be a factor which decreases the quality of sports performance, especially during competition. The aim of this study was to identify situations which generate the highest stress levels in karate contestants. Material/Methods: Polish National Kyokushin team members (n=22) participated in the study. Questions concerning training and competitions were answered on a 10 – point scale. Cronbach alfa for questionnaire items were 0.84–0.97. Stress demand level was determined by sports motivation questionnaire. Mean values of males and females were compared by non-parametric tests (p£0.05). Results: Competitions generated higher stress than training. Importance of competition and presence of audience increased stress intensity. Quality of fighting activities modified stress intensity. Stress intensity at the end of karate match remained lower in men than women. Stress during the first selection match and semi-final fight exceeded athletes’ general demand for stress. Stress intensity was lower than the demand for stress during tactical and technical training, free of audience. The dissonance between stress intensity and demand for stress in women in final fights, against stronger opponent, exposed them to psychological discomfort. Conclusions: Psychological and tactical preparations correlate. This manifests by development and realization of a fight plan and reaction to unexpected situation. Differences in reactions between men and women in stressful situations suggest the need for individual approach to training process and at each stage of competition.

Evaluation of Sex-Specific Movement Patterns in Judo Using Probabilistic Neural Networks

The purpose of the present study was to create a probabilistic neural network to clarify the understanding of movement patterns in international judo competitions by gender. Analysis of 773 male and 638 female bouts was utilized to identify movements during the approach, gripping, attack (including biomechanical designations), groundwork, defense, and pause phases. Probabilistic neural network and chi-square (χ2) tests modeled and compared frequencies (p ≤ .05). Women (mean [interquartile range]: 9.9 [4; 14]) attacked more than men (7.0 [3; 10]) while attempting a greater number of arm/leg lever (women: 2.7 [1; 6]; men: 4.0 [0; 4]) and trunk/leg lever (women: 0.8 [0; 1]; men: 2.4 [0; 4]) techniques but fewer maximal length-moment arm techniques (women: 0.7 [0; 1]; men: 1.0 [0; 2]). Male athletes displayed one-handed gripping of the back and sleeve, whereas female athletes executed a greater number of groundwork techniques. An optimized probabilistic neural network model, using patterns from the gripping, attack, groundwork, and pause phases, produced an overall prediction accuracy of 76% for discrimination between men and women.

Somatotype components in judoists

Sport theoreticians and practitioners predominantly agree that the choice of a particular sport by a candidate should be based on their individual aptitudes (physical, psychological, somatic) [1,2]. It is emphasized that the athletes with potential for success in sport should be found through “careful elimination” in direct “back-up” groups in national teams [3]. Body height can be estimated according to regression equations [4]. The body composition, width and circumference dimensions can be improved through sport training and competitions [5,6], but there is a lack of high-quality updated international evidence concerning somatotypes, which are becoming more and more important in selection of talented individuals in judo. This analysis aimed to review the contemporary scientific output in the field of somatotypes and judo. The analysis encompassed the data contained in the da tabases of Academic Search Complete, Elsevier, Sportdis cus, Medline. Searching and reviewing relevant references and review articles helped identify 21 studies involving 574 male judoists in total. In all the studies, the methodology of somatotype identification by Carter and Heath [6] was used and mean somatotypes were presented. The mean somatotypes were presented in a somatochart. At the next stage of the analysis, 5 publications were excluded because they failed to present standard deviation values, which are necessary for comparative analysis of means (ANOM). Somatotype components (endomorphy, mesomorphy, ectomorphy) were analyzed using analysis of means (ANOM method) (16 samples involving 311 seniors). The chart allowed for the determination of the grand mean and upper (UDL) and lower (LDL) decision limit, useful for interpretation of statistical significance of the differences between the means from each study group and the grand mean [7]. Differences were confirmed by the analysis of variance ANOVA and Bonferroni’s multiple comparison test. In addition five samples of female judoists were analysed.

Effect of Acute Effort on Isometric Strength and Body Balance: Trained vs. Untrained Paradigm

Years of training in competitive sports leads to human body adaptation to a specific type of exercise. In judo bouts, maintaining hand grip on an opponent’s clothes and postural balance is essential for the effective technical and tactical actions. This study compares changes after maximal anaerobic exercise among judo athletes and untrained subjects regarding 1) maximum isometric handgrip strength (HGSmax) and accuracy at the perceived 50% maximum handgrip force (1/2HGSmax) and 2) the balance of 13 judo athletes at national (n = 8) and international (n = 5) competitive levels and 19 untrained university students. The groups did not differ in age, body height, and weight. Body mass index (BMI) and body composition (JAWON) were evaluated. The Wingate Anaerobic Test (WAnT, Monark 875E) measured recommended anaerobic capacity indices. Hand grip strength (Takei dynamometer) and balance (biplate balance platform) were measured before warm-up (T1), before the WAnT test (T2), and after (T3). Parametric or non-parametric tests were performed after verifying the variable distribution assumption. Judoists had higher BMI and fat-free mass index (FFMI) than the students. The athletes also showed higher relative total work and relative peak power and lower levels of lactic acid. The difference in judoists between HGSmax at T1 and HGSmax at T3 was statistically significant. Before warm-up (T1), athletes showed higher strength (more divergent from the calculated ½HGSmax value) compared to students. Substantial fatigue after the WAnT test significantly deteriorated the body stability indices, which were significantly better in judo athletes at all time points. The findings suggest specific body adaptations in judoists, especially for body composition, anaerobic energy system efficiency, and postural balance. These characteristics could be trained for specifically by judo athletes to meet the time-motion and anaerobic demands of contemporary bouts.