Thesis (M.S.)--Baylor University, 2006. / Includes bibliographical references (p. 56-62).

Table tennis playing involves complex spatial movement of the racket and human body. It takes much effort for the novice players to better mimic expert players. The evaluation of motion patterns during table tennis training, which is usually achieved by coaches, is important for novice trainees to improve faster. However, traditional coaching relies heavily on coaches qualitative observation and subjective evaluation. While past literature shows considerable potential in applying biomechanical analysis and classification for motion pattern assessment to improve novice table tennis players, little published work was found on table tennis biomechanics. To attempt to overcome the problems and fill the gaps, this research aims to quantify the movement of table tennis strokes, to identify the motion pattern differences between experts and novices, and to develop a model for automatic evaluation of the motion quality for an individual. Firstly, a novel method for comprehensive quantification and measurement of the kinematic motion of racket and human body is proposed. In addition, a novel method based on racket centre velocity profile is proposed to segment and normalize the motion data. Secondly, a controlled experiment was conducted to collect motion data of expert and novice players during forehand strokes. Statistical analysis was performed to determine the motion differences between the expert and the novice groups. The experts exhibited significantly different motion patterns with faster racket centre velocity and smaller racket plane angle, different standing posture and joint angular velocity, etc. Lastly, a support vector machine (SVM) classification technique was employed to build a model for motion pattern evaluation. The model development was based on experimental data with different feature selection methods and SVM kernels to achieve the best performance (F1 score) through cross-validated and Nelder-Mead method. Results showed that the SVM classification model exhibited good performance with an average model performance above 90% in distinguishing the stroke motion between expert and novice players. This research helps to better understand the biomechanical mechanisms of table tennis strokes, which will ultimately aid the improvement of novice players. The phase segmentation and normalization methods for table tennis strokes are novel, unambiguous and straightforward to apply. The quantitative comparison identified the comprehensive differences in motion between experts and novice players for racket and human body in continuous phase time, which is a novel contribution. The proposed classification model shows potential in the application of SVM to table tennis biomechanics and can be exploited for automatic coaching.

De pertinents travaux analysent l'impact du sport dans notre société, répartissant en différentes catégories ses agents, étudiant sa marchandisation ou s'intéressant encore à ses formes les plus extrêmes, voire les plus élitistes. Mais que peut-on dire des effets produits par cet objet du point de vue de sa transmission ? Comment décrire les rapports parfois paradoxaux entre la modélisation institutionnelle de la diffusion du sport et sa réalité quotidienne ? Si plus précisément on s'intéresse à la pratique du tennis en France, il est possible d'établir trois constats fondamentaux. Premièrement, ce jeu est un loisir « majeur » : en 2014 la fédération française de tennis (FFT) comptabilisait plus d'un million de licenciés, ce qui faisait du tennis le second sport national, derrière l'intouchable football. Dans un second temps, cette activité est désormais accessible à des publics qui jusqu'ici en étaient relativement exclus. Ce phénomène fut traduit – de façon quelque peu erronée – de « démocratisation ». Enfin, lorsqu'on observe de plus près ce qui se passe dans les clubs, on s'aperçoit que les adeptes du tennis sont de plus en plus nombreux à pratiquer ce sport sous la coupe d'une sorte d' « entraineur ». Ce dernier est chargé de parfaire leur maitrise de la discipline, voire de façon plus implicite, de réduire les contraintes classiques du joueur de club (trouver un partenaire, organiser une partie, etc...). Cette thèse – à la croisée d'une sociologie du loisir, du sport, des professions, du corps et de l'expertise – s'intéresse principalement à cette dernière tendance. Ce que nous désignerons comme la « pratique encadrée du tennis » s'érige comme une modalité de jeu moderne et désormais pleinement normalisée dans les clubs. Notre enquête dresse alors la chaine sociale qui produit ou permet la tenue de ce qu'Erving Goffman désigne comme une « relation de service », avant de décrire de ses usages et de ses effets du point de vue des individus qui la vivent. La démarche est sociographique, elle conjugue une nécessaire distanciation sur l'objet et une « participation observante » établie sous différentes postures (« élève », « encadrant », observateur, ou encore simple confident). L'étude se divise en trois phases qui traitent notre objet de sa normalisation dans le paysage sportif contemporain, jusqu'aux expériences individuelles qui en émanent. / If, in a sociological point of view, you look at the way tennis is played in France, you can make three fundamental observations. First, it,'s a very popular hobby : in 2014 the French tennis federation (FFT) counted up to one million one hundred thousand members, making tennis the second national sport, behind the unreachable footbal. Second, this activity is now accessible to people who were rather excluded until then. This phenomenon has been quite inaccurately described as « democratization ». Finally, if you observe the clubs, you realize that more and more tennis players practice this sport under the supervision od a coach. The latter is in charge of perfecting their skills, or sometimes enven more iplicity of making their practice easier by finding them a partner or arranging a match for example. This thesis is at cross-road between a sociological analysis of leisure activities, sport, carrer, body and, above all, expertise. What is here called « the supervised practice of tennis » refers to a modern playing method that is now standard in clubs. This enquiry depicts the social mechanism that produces or enables what Erving Goffman refers to as « a service relationship » and then it use and effects from the point of view of those who experience it. This is a sociographical approach that combines a necessary detachment from the subject and a participation combined with a watchful observation from different positions. The enquiry is divided into three phases, dealing with the object from its normalization in the modern sporting landscape, to the personal experiences in which it results

The sound radiated during a tennis impact has been shown to greatly influence the perception of 'feel' but has also been suggested to contribute to the perception of equipment quality, as is the case with many other consumer products. In an industry that is governed by design limitations, tennis racket manufactures are continually aiming to differentiate their products from their competitors' and the sound character of a racket is seen as one such method to do so. In order to control the sound radiated from a tennis racket it was first necessary to identify how a tennis racket radiates sound. Through a number of controlled player tests, involving groundstrokes and serves, the sound was recorded along with measurements of the physical vibrations excited in the frame. Analysis of the data revealed typical characteristics of the sound in the time and frequency domain. The sound was split into two sections to aid the analysis; an initial impulsive component that decayed very quickly and a ringing component that was of much lower amplitude but decayed at a much slower rate. The evolution of the frequency content over time was also investigated, however, the data provided much more information as to where each frequency component originated by analysing the data together with the experimental modal analysis data. The experimental modal analysis of a tennis racket was a vital stage in understanding which components of the racket were responsible for radiating the identified frequency component in the sound spectrum. The investigations identified frame bending modes, out-of-plane and inplane, as well as torsional modes, hoop modes and stringbed modes. To enable direct comparison between the natural frequencies excited during a tennis shot and the frequencies recorded from a freely suspended racket, the effect of the hand on the modal behaviour of the racket was analysed; experimental modal analysis data from a hand-gripped racket was compared with data generated by adding simulated mass to the modal model of the freely suspended racket. The first stringbed mode was identified as a key contributor to the sound of the racket, especially in the ringing component of the sound. Analysis of the physical vibrations in the frame following a tennis shot revealed that the first stringbed mode excited the frame of the racket, which is iv thought to be the reason why stringbed modes contribute to the sound more so than their surface area would suggest that they are capable of. Analysis of the relationship between subjective perceptions of players and calculated sound metrics suggest a negative correlation exists between the duration and loudness of a tennis shot and the appeal of the sound. Further investigations involving a jury to evaluate the appeal of a tennis impact sound, modified in terms of duration, revealed further evidence to support the theory that tennis impact sounds of greater duration are less appealing than those that decay quickly. This is the first study to investigate the sound radiated from a tennis racket and has identified how the sound is radiated from the racket and also suggests which parameters of the sound are considered appealing to tennis players. With this information it is possible to suggest design modifications that would influence the sound of a tennis racket in a predictable manner.

In sports, one might wish to test new ideas regarding player movement, tactics, or strategy without subjecting the athletes to possibly wasteful or even harmful habit formations. If a method of simulation of the athlete can be devised, experiments might reasonably be conducted to evaluate the ideas independently of actual training or trial in the field. Simulation of a complex system generally begins with a long period of analysis. During this time there may be mathematical and programming explorations and constructions to sharpen and examine different approaches. Meetings are usually held by the participants to try to define the task and explore alternatives. Ideas are amplified, possibly discarded as not feasible, or incorporated into the system package. Gradually there evolves a tighter and more acceptable formulation using logical and mathematical expressions (Preface, p. vii)

M.Tech. / Purpose: Lateral epicondylitis has been identified as one of the most common conditions affecting the upper limb. The exact pathophysiology of this condition is still under investigation; however it is believed to be an overuse injury which affects the common extensor tendon at the tenoperiosteal and/or the musculotendonous junctions. Despite the frequent occurrence of lateral epicondylitis and its considerable symptoms there is little scientific evidence to support the effectiveness of any treatment methods. As yet one treatment method has not been proved more effective than the other. The purpose of this comparative study was to determine whether manipulation combined with dry needling of the common extensor tendon and extensor muscle belly of the forearm, was more effective than cross friction of the common extensor tendon combined with manipulation with regards to a decrease in pain and an increase in pressure pain threshold. Method: This study consisted of 32 participants between the ages of 18 – 40. Possible participants were examined and accepted according to the inclusion and exclusion criteria. Once accepted the participants were assigned into two groups each consisting of equal amounts of males and females. The first group received manipulation of their elbow combined with dry needling of their common extensor tendon and extensor muscle belly of their forearm. The second group also received manipulation of their elbow but this was combined with cross friction of their common extensor tendon. Procedure: Each participant received six treatment sessions and one follow up session. Objective data and subjective data was taken at the beginning of the first, fourth and seventh session. Objective data consisted of algometer readings that were taken on the common extensor tendon, the lateral epicondyle of the humerus and the extensor muscle belly. The subjective data collected was in the form of the Numerical Pain Rating Scale and the short form of the McGill Pain Questionnaire. The manipulation of the elbow was then administered based on the restrictions identified during motion palpation. This was followed by either dry needling of the common extensor tendon and the extensor muscle belly of the forearm or cross v friction of the common extensor tendon. The information collected was analysed by means of Friedman and Wilcoxon Signed Rank tests.Results: Statistically significant improvements in all measurements were noted over the course of the treatments for all participants in both groups. However there was no statistically significant difference between the improvements of the dry needling group compared to that of the cross friction group. Conclusion: The results illustrate the effectiveness of the individual treatments over the treatment period. However it is still inconclusive whether one treatment method is more effective than the other. As this study was directed to a small group of participants, accurate conclusions could not be formulated to prove the effectiveness of one treatment method over that of another. Due to the insignificant findings obtained in this study, further studies need to be performed to determine which method of treatment is most effective when treating lateral epicondylitis.

Title: Strategy and tactics in tennis singles Objectives: The primary goal of this study was to inquire, at various levels of the training process, into what elite tennis players require from their coaches in order to maximize the outcomes of the training process. The secondary goal was to supply the perspective of the players with a perspective obtained from experienced tennis coaches. The coaches provided us with their views on what makes the training process effective. Methods: The research design of this study is a version of the multi-case explorative study that gathers data by means of semi-structured interviews. It is a case of qualitative research. The data obtained, in total from 18 respondents (9 players, 9 coaches), were submitted to a deductive form of thematic analysis. Two thematic tables and the related reports are the outcomes. The reports were made with the intention of formulating useful recommendations, whenever possible, and to relate the findings to the content of the theoretical part of the thesis. Results: Our data have underpinned the importance of tactics training. To maximize the effectiveness of the training process, it has been reported, it is necessary to bring the training process in terms of performance, in various aspects (tactics, psychology, physical performance...

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