Biomechanics and parasports. Conceptual model of performance ergonomics in manual wheelchair

At the last Paralympic Games, athletes' performances improved considerably, not only thanks to the quality and quantity of their training methods, but also, and above all, to the evolution of the equipment used. Today, the configuration of the manual wheelchair (FRM, as distinguished from electric wheelchairs) has become increasingly specialized to meet the requirements and particularities of different sporting disciplines. Numerous biomechanical studies of propulsion in sport FRMs have investigated the influence of different settings on performance. But the importance of these performance criteria differs not only from sport to sport, but also from athlete to athlete. Indeed, extracting knowledge from expert athletes shows that the choice of chair settings and the importance of performance criteria depend on the athlete's physical capabilities.

However, numerous authors have highlighted the particularly restrictive nature of handrail wheelchair (HW) propulsion, both in musculoskeletal and cardiorespiratory terms. That's why, over the last thirty years or so, the scientific community has shown renewed interest in alternative propulsion modes to FMC. Among these, crank propulsion is the only alternative propulsion mode to have really taken off. This type of propulsion is also known as "handbike" (hereinafter HB), "tricycle" or "handcycle". The advantages of crank propulsion over handrail propulsion are not confined to metabolic parameters: it is also less demanding on the musculoskeletal system. It would also enable better application of force and more continuous arm movement.

In this article, two types of FRM will be studied: the basketball wheelchair (chair with handrails) and the handbike (wheelchair with cranks). The focus of this article is on propulsion technology and the ergonomic aspects of wheelchair adjustments (in line with the user), in order to improve performance and reduce injury risk factors associated with this mode of propulsion. This article is based on a conceptual model illustrating the main factors influencing the ergonomics of sports wheelchair performance. This conceptual model demonstrates the need for an interdisciplinary approach by highlighting the physiological and biomechanical factors associated with the "sports wheelchair-user" interaction that ultimately influence the ergonomics of wheelchair sports performance. To meet this objective, various tools for assessing the biomechanical parameters of FRM propulsion have been developed.