Opale Vigié

In the context of wheelchair racing, research primarily focuses on studying wheelchair ergonomics and determining kinematic, kinetic, and rolling resistance variables. One factor identified as influencing athletes’ performance is wheel skidding on the ground, a parameter complementary to rolling resistance. The objective of this study, therefore, is to identify, within a laboratory setting, the parameters that influence the risk of skidding in racing wheelchairs by measuring skidding torque. The ultimate goal is to enhance athletes’ performance by optimizing the interaction between the athlete and their wheelchair, and the wheelchair and the environment. In this perspective, four parameters were examined: the type of tubular, the camber angle, the tire pressure, and the load applied to the wheel using a skidometer. This tool characterizes a tire’s grip on a surface by measuring torques. The aim is to develop a system for classifying tire grip on dry athletics track at ambient temperature. The findings revealed that only the effects of load and tubular type had a significant impact on the torque values obtained. The tire that minimized the risk of skidding, among all tested combinations, is the Vittoria Pista Speed 23–28″. Furthermore, as the mass applied to the wheel increases, so do the resulting torques. This implies that a heavier athlete would require a greater force to be applied to the hand rim for the tire to skid. However, it was also demonstrated that the risk of skidding in a racing wheelchair is unlikely, as the torques obtained were over a range of 90 to 190 Nm. These values far exceed those typically exerted by para-athletes, which are a maximum of 60 Nm. The long-term goal would be to adjust the mode of torque application on the wheel using the skidometer for a more realistic field approach.

Measuring the propulsion performance of sport wheelchairs in ecological conditions remains complex due to variations inherent in real-world practice. This study aims to develop a validation protocol for an instrumented wheel designed to measure propulsion power under ecological conditions. The wheel’s precision was compared to that of the Lode Esseda roller ergometer, the gold standard for measuring the force exerted on both the left and right hands. Tests were conducted at three speeds (1, 2, and 3 m/s) on a multisport wheelchair. Results show a strong correlation between the two systems, confirmed by a repeated measures ANOVA test (p > 0.05) and a root mean square error (RMSE < 5%). Bland–Altman plots reveal good agreement despite discrepancies observed at high speeds, potentially due to mechanical limits. The proposed protocol validates the instrumented wheel and highlights the importance of multi-speed evaluation to ensure valid measurements in ecological conditions.