• Herbert Hatze
Keywords: biomechanical modelling, performance optimization


The performance criteria of physical activities, especially those of sport disciplines, can usually be defined in biomechanico-mathematical terms. This implies that sufficiently complex models of the human neuromusculoskeletal system can be used for the simulation and analysis of sports motions and, at least in principle, for the biomechanical optimization of the performance in the various sport disciplines. It is frequently forgotten that biomechanical optimization, in the widest sense, is the ultimate goal of the majority of all endeavors in sports biomechanics, even if this may not always be obvious. Examples of the successful generation of biomechanical models include adequate models of the human skeletal and muscular subsystem, and the creation of a functional racket-hand-arm system model for simulating tennis strokes. Simultaneously, anthropometrico-computational and dynamometric methods were developed for determining respectively the subject-specific segmental and myodynamic parameter sets. The models and methods just mentioned will be illustrated during the oral presentation. As regards the practical applications of the biomechanical modelling approach to sports, some selected examples also to be presented are: the complete optimization of a kicking motion; the successful computer simulation and analysis of a rock ' n roll Betterini somersault in connection with an accident requiring a biomechanical expert opinion; the development of an objective biomechanical method for testing the quality criteria of tennis rackets; the quantification of the variability of repeated sports motions; and investigations into the validity and reliability of vertical jumping performance testing methods. Needless to say that appropriate biomechanical models of the human neuromusculoskeletal system are indispensable in theoretical studies such as the demonstration of the comparatively high insensivity of skeletal motions to neural control perturbations. Considering the current state of the art it would appear that contemporary biomechanics of sports is still too pre-occupied with measurement, data collection, and the subsequent phenomenological description of an observed event instead of asking the (much more difficult) question concerning the causes and fundamental mechanisms underlying the observed phenomenon. The mere measurement and description of the ground reaction forces during the release phase of the javelin throw, for instance, without relating their significance to the musculoskeletal factors that determine the throwing distance, is meaningless and constitutes a futile exercise. As a future trend in sport biomechanics, the utilization of models for performance optimization may be expected to gain increasing importance.