Search

Background: An interesting and little-reported problem in the literature is the scale of asymmetry in table tennis players, the magnitude of which should perhaps be treated as a risk for injury. Determining the degree of asymmetry in table tennis players can indicate the need to appropriately manage the training process, including compensatory or corrective exercises in the training program, especially since recent studies confirm that training interventions can reduce sporting asymmetries and improve performance. This study aimed to assess the amount of asymmetry in the trunk regarding the frontal plane and the difference between limb circumferences in female table tennis players compared to the control group (non-athletes). Methods: Twenty-two women took part in the study. Ten of them were table tennis professionals with an average training experience of 7 ± 4.3 years (the exclusion criterion of the study was a minimum of 3 years of training experience). As a comparison group, the study included 12 female students who did not participate in competitive sports. Body posture was assessed in all subjects using equipment for computer analysis of asymmetry in the torso using the photogrammetric method. Additionally, all the subjects had their upper and lower limb circumferences measured. Results: The results of the conducted research showed asymmetry in the frontal plane in the table tennis player group. As many as six parameters—regarding the pelvic rotation angle, angle of trunk inclination, the height of the angles of the lower shoulder blades and their distance from the spine, as well as the waist triangles, difference in the width and height of the waist triangles and the angle of trunk inclination—indicated asymmetry in this group but significantly differed from the control group (p ≤ 0.05) only in the first parameter given above. The calculated differences in circumference between the right and left sides in the individual groups were statistically different in several cases (p ≤ 0.05). This concerned the circumferences of the arms, forearms, elbows, and knees of table tennis players. Conclusions: The research carried out in this study allowed us to determine the occurrence of asymmetry in the frontal plane of the trunk and between the limbs of table tennis players. According to some studies, this may be a risk factor for injury. However, despite the lack of uniform views in the literature on the importance and threats resulting from asymmetries, it appears that, if only for aesthetic reasons, table tennis would require compensatory or corrective training aimed at developing symmetry of the body structure. [ABSTRACT FROM AUTHOR]

The aims of this study were to evaluate movement patterns of topspin forehand, to define the main principles of performing this shot, and to determine the essential differences in individual types of topspin forehand. In total, 10 female high-level athletes participated in this study. The BTS analysis system was used with a novel model for the range-of-motion measurement. An acoustic sensor was attached to the racket for identification of a ball-racket contact. Players, performing topspin forehand, attempt to achieve maximal racket velocity based on the principles of proximal-to-distal sequences and summation of speed with a stretch-shortening character of cycle. The essential differences between type of topspin forehand occurred in the range of motion. Increased power of topspin shot was accompanied by a significant increase in range of motion in most of the studied joints and body segments, in particular in the rotation movement of the upper body, pelvis and shoulders, flexion and rotation in the shoulder and elbow joints, and flexion and rotation in knee joints. [ABSTRACT FROM AUTHOR]

The aims of the research were to (1) determine the values of kinematic parameters in two modifications of the topspin forehand stroke as well as the differences between them and (2) assess the inter-individual and intra-individual variability of the values. Two modifications of a topspin forehand were evaluated: topspin after a topspin ball (TF1) and topspin after a backspin ball (TF2). The MyoMotion Noraxon analysis system was used to record the kinematic data. A piezo-electric sensor was used to identify the moment when the ball made contact with the racket. The coefficient of variation determined the variability of the kinematic parameters. Most of the joint angles in four identified events reflected how the individual segments of a player's body should move. The difference in acceleration at the moment of contact between the two types of the topspin forehand was significant, but the variability of the acceleration values was small. Large variability in the angular parameters was found, and this result was considered a manifestation of different coordination patterns in the stroke movements. It is possible that even though the players used different methods of performing the movement, they obtained similar values for some parameters (e.g., acceleration), which should be taken into account by coaches. There were small differences in many parameters within individual players, which can indicate that a player performs tasks in a similar way each time. However, there was high variability in some angular parameters, indicating that the repetitions of particular strokes were not performed in an identical way. The reasons for this phenomenon include movement functionality and functional variability. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the correlations between angular velocities in individual joints and racket velocity for different topspin forehand and backhand strokes in table tennis. Ten elite female table tennis players participated, presenting different kinds of topspin forehands and backhands -- after a no-spin ball (FH1, BH1), after a backspin ball (FH2, BH2) and "heavy" topspin (FH3, BH3). Range of motion was measured with the BTS Smart-E (BTS Bioengineering, Milan, Italy) motion analysis system with a specially developed marker placement protocol for the upper body parts and an acoustic sensor attached to the racket to identify ball-racket contact. In forehand strokes angular velocities of internal arm rotation and adduction in shoulder joint correlated with racket velocity. Racket velocity was correlated with angular velocities (hip extension on the playing side; hip flexion on the opposite side; ankle flexion) in the case of a topspin forehand performed with maximal force --"heavy" topspin (FH3). In backhand strokes the velocities of arm abduction and shoulder girdle rotation towards the playing side correlated with racket velocity. The angular velocity of internal arm rotation and adduction in shoul- der joint may be important components of a coordinated stroke, whilst angular velocity can substantially affect the racket speed when one is changing the type of stroke. [ABSTRACT FROM AUTHOR]

Introduction. Studies have proven that the level of proprioceptive ability is related to motor learning. Many authors also indicate the importance of proprioception in sports and have reported the existence of a correlation between kinesthetic differentiation abilities and success in different sports. Aim of Study. The aim of the study was to evaluate the accuracy of reproduction of the range of movement for forearm pronation and supination in the elbow joint as well as the level of hand pressure force in table tennis players, soccer players and non-training subjects. The study also attempted to examine changes in the level of this accuracy after six months of training. Material and Methods. The study was conducted on groups of table tennis players (10), soccer players (10), and non-training controls (10), aged 14.5 years. The participants undertook six tasks demonstrating their level of proprioceptive ability: accuracy of recreating pronation and supination of the forearm at the elbow joint; and accuracy of recreating hand pressure force. The test was carried out twice during the year. Results. The results revealed small differences between the groups after the first test and more significant differences after the second test. The soccer players showed a higher level of proprioceptive ability than the other two groups of participants. Conclusions. This study points to the significance of proprioceptive ability in soccer. The results of proprioceptive tasks are varied and depend on multiple factors, which is probably typical for this ability. [ABSTRACT FROM AUTHOR]

Introduction: Kinesthetic differentiation is frequently reflected in table tennis skills such as making an appropriate racket angle, adjustment of force and speed of arm movement upon hitting the ball, quick assessment of the arm position in reference to the ball, and making decisions about appropriate adjustments or changes. The level of kinesthetic differentiation of table tennis players should be fairly high. Aim of Study: The aim of this research was to assess and compare the accuracy of hand pressure force and range of supination -- pronation reproduction in female table tennis players representing different sports levels, and in girls who did not practice table tennis. Material and Methods: The research was conducted on 32 female subjects: a group of table tennis players (n = 20) and a control group (n = 12). The subjects took part in six tasks aiming to demonstrate their levels of kinesthetic differentiation. Four of the tests enabled the assessment of accuracy of recreating pronation and supination of the forearm at the elbow joint. Two other tasks evaluated the force components and assessed the precision of recreating hand pressure force. Results: The precision indices for pronation performed with the dominant limb attained by the table tennis players were the lowest (i.e. the best) for those representing the highest sport level. The results of tasks designed to evaluate the ability of kinesthetic differentiation were slightly better for the table tennis players than for the control group. Conclusions: A statistically significant difference was observed only in supination of the dominant limb. This task may be specific to table tennis since the greater precision in the range of the dominant limb results from the use of the dominant arm in the game. The best results in supination of the dominant limb were obtained by the most advanced group of players with the longest training experience, which may indicate a correlation between kinesthetic differentiation and sports level in table tennis. KEYWORDS: proprioception, kinesthetic differentiation, joint position sense, force sense, table tennis. [ABSTRACT FROM AUTHOR]

Introduction. Badminton is considered a sport requiring high levels of all constituent speeds. Few available instances of research in this area maintain that badminton players are characterised by high levels of movement speed, nervous conductivity and agility. Aim of the Study. This work was aimed to determine the times of simple reaction in male and female badminton players by assessing differences between badminton players and controls. Assessment of reaction times also involved a comparison of results obtained during the experiments with standards available in the literature. Material and Methods. Subjects were divided into four groups: two groups of top level junior players (10 boys and 6 girls); 26 non-playing boys and 6 non-playing girls. The measurements were conducted with the use of the MRK-80 reaction meter. Results. Arithmetic means, minimum and maximum values, standard deviation and coefficient of variation were calculated. Student's t-test was conducted to compare the results in the groups. Conclusions. Badminton players display shorter reaction times than non-players, which is probably the consequence of practicing badminton. The difference was found between results of all tests taken by boys and most tests taken by girls. The comparison of the obtained reaction times displayed by badminton players with the available standards proved that their values were mostly average, which might be the consequence of the fact that in badminton, like in many other sports, more complex factors, e.g. choice reactions, anticipation, etc., are of far greater significance. [ABSTRACT FROM AUTHOR]

Kinesthetic differentiation ability in table tennis is probably most reflected by abilities connected with playing precision such as control of ball rotation, modulation of force, speed and direction of shots, and choosing the optimal racquet angle. The aim of the study was to evaluate changes in the level of kinesthetic differentiation ability in table tennis players. The study sample consisted of 19 young table tennis players. Kinesthetic differentiation ability was evaluated with the use of goniometric tests (measurement of task movement range), performed twice during the year. The performance of the majority of tasks showed that the precision of reproduction improved in young male table tennis players, which may point to the significance of this ability in this sport. Progress in some tasks is probably attributed to those task movement tests which are more specific to table tennis (movement range and direction). [ABSTRACT FROM AUTHOR]

Background. Kinesthetic differentiation ability in table tennis is most probably reflected by abilities connected with playing precision such as: controll of ball rotation, modulation of force, speed and direction of shots and choosing the optimal racquet angle. The aim of the paper was to evaluate relationship between laboratory-measured kinesthetic differentiation ability and the results of play precision tests. Material and methods. The study involved 20 female and 41 male table tennis competitors. Kinesthetic differentiation ability was evaluated with use of goniometric tests (measurment of task movement range) and kinesthesiometric tests (measurment of task force intensity). Precison of table tennis play was evaluated on the base of play tests. Results. The study revealed numerous statistically significant correlations between kinesthetic differentiation ability test results and precision of play. The results of majority of play tests significantly correlated with many task movement tests, especially in men. Conclusions. Stronger correlations with play precision are probably attributed to those task movement tests which are more specific to the disciplin (movement range and direction, direction of force, so called „playing" extremity). The diversity of revealed correlations is probably derived from heterogenicity of kinesthetic differentiation abilities and many other factors not formulated in the paper which could influence precision of table tennis play. [ABSTRACT FROM AUTHOR]