Zehn Probanden führten Niedersprünge aus drei verschiedenen Höhen durch. Dabei wurden sie per Video gefilmt und es wurden mit Kraftplattformen Messdaten aufgezeichnet. Die Werte, die die Auftreffkräfte kennzeichnen, wurden aus Bodenreaktionskräften und den Gelenkmomenten der unteren Extremitäten in Relation zu den Veränderungen des Landemoments berechnet. Die Korrelationen zwischen der Auftreffkraft und dem Landemoment wurden genutzt, um die Reaktionen der Probanden einer entweder positiven oder negativen biomechanischen Strategie zuzuordnen, wie sie im für das Experiment eingesetzten Model definiert wird. Es zeigte sich auch, dass die Probanden - mit einer Ausnahme - den Einsatz einer positiven oder negativen Strategie von einzelnen Faktoren abhängig machten, durchaus zwischen ihnen wechselten, wenn sich die Bedingungen veränderten. The purposes of this study were to (a) present a theoretical model to explain the methods by which individuals accommodate impact force in response to increases in an applied stressor, (b) use the model and a correlation procedure to classify a sample of individuals based on their observed response patterns, and (c) statistically evaluate the classification process. Ten participants performed landings from three heights while video and force platform data were being collected. Magnitudes of impact-force characteristics from ground reaction force and lower extremity joint moments were evaluated relative to changes in landing momentum. Correlation between impact force and landing momentum was used to classify participant responses into either a positive or negative biomechanical strategy, as defined by the model. Positive and negative groups were compared using the Mann-Whitney U test. Results indicated that all responses fit within the categories defined by the model. Some individuals preferred positive strategies while others preferred negative ones depending on the specific variable. Only one participant consistently exhibited the negative strategy for all variables. Positive and negative groups were determined to be statistically different, p £ 0.05, for 61% of the comparisons, suggesting actual differences between groups. The proposed model appeared robust and accounted for all responses in the current experiment. The model should be evaluated further using landing and other impact activities; it should be refined and used to help researchers understand individual impact-response strategies in order to identify those who may be at risk for impact related injuries.
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