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arXiv · 2608.22507

What is the effect of running-specific prostheses on long jumps? Optimization-based prediction and analysis using biomechanical models

Anna Lena Emonds·Johannes Funken·Wolfgang Potthast·Katja Mombaur
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Abstract

Long jumpers with below the knee amputation (BKA) that take off from their running-specific prosthesis (RSP) improved performances significantly over the last years. The long jump biomechanics differs compared to athletes without BKA and the question arises whether the spring-like properties of the RSP facilitate achieving long jumping distances. The aim of this work is to propose a long jump model for athletes with and without BKA, to evaluate it and to apply it for comparing long jump motions with and without RSP. We establish rigid multi-body system models of one athlete with and one athlete without below the knee amputation (BKA). Long jump motions are computed by solving a specific optimal control problem (OCP) with constraints enforcing a physically correct dynamics, both for motion reconstruction or motion synthesis. With the proposed long jump model, we are able to compute realistic long jump motions. We discuss the causes of differences in measured long jumps and show directions for eliminating them. For both athletes, the synthesized solutions reveal potential for performance improvement. The jumping distance of the athlete without BKA is 64cm (6.9%) longer than the one of the athlete with BKA in the synthesized solutions.

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Anna Lena Emonds, Johannes Funken, Wolfgang Potthast, Katja Mombaur. 2026-08-23. What is the effect of running-specific prostheses on long jumps? Optimization-based prediction and analysis using biomechanical models. https://arxiv.org/abs/2608.22507

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