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Prescription of wheelchair rugby chairs is difficult due to the range of athlete impairment types and severities in the sport, difficulty in adjusting wheelchair settings, and assessing on-court performance. Currently, elite players rely on experiential knowledge (personal, coaches, and support staff) to select an appropriate set-up. Technological advancements, such as with inertial measurement units and processing algorithms, and representative testing approaches, has improved the potential for assessing set-ups at an individual level. An orthogonal design approach was implemented using an adjustable wheelchair to investigate the effect of seat height, seat depth, seat angle, and tyre pressure on performance, mobility, and propulsion kinematics. Six elite wheelchair rugby players completed testing in nine individually tailored wheelchair set-ups while monitoring both quantitative and qualitative measures of performance. From this testing, a recommended set-up was compared with the current set-up for each individual. A single case-study approach shows how the assessment method identifies parameter settings that can potentially improve performance. Three of six players reported a blind preference for the recommended set-up over the current set-up, whilst remaining players often displayed similar performance between their current and recommended set-ups. This approach can improve upon the current prescription process for rugby wheelchairs.

Due to the detrimental influence of unnecessary mass on performance, racing wheelchair instrumentation used in both competition assessment and research is currently limited. Attaining key kinetic parameters of propulsion can enhance technique and provide athletes with a competitive advantage. This research examined the plausibility of inertial measurement units (IMUs) to estimate propulsion forces, during a simulated wheelchair race start and training. Start propulsion data calculated from an IMU system was compared to reference force plate data; steady state motion data was compared with existing literature. Some agreement in kinetic parameters between IMU data was observed under steady state motion, with data from athletes following a linear force-velocity relationship. In this context, it is important to identify that this cannot be directly compared to the existing literature due to the different methods of force measurement and the lack of data for similar force measurements using IMUs. IMUs were ineffective when used with wheelchairs having spoked wheels. Performance was best for measurements in the direction of motion. Although exact agreement was not observed, the IMU can provide an effective tool in the in-field assessment of propulsion kinetics.

Objectives: Use a task vehicle of sprint testing in wheelchair rugby (WCR) to explore the impact of small changes to test design using both group and individual analysis., Design: Exploratory, repeated measures, on-court study METHOD: 25 national or international level wheelchair rugby players completed 5×5m sprints under two conditions: (i) an acceleration from standstill in their own time, and (ii) an 'active' start, simulating a key aspect of performance. Video analysis and accelerometer data were used to measure key kinematic and performance variables with a focus on the first three strokes. Each player was grouped into a high-, mid-, or low-point group based on their sport-specific classification score. Group (paired sample t-tests) and individual (meaningful differences, performance coefficients, and Cohen's d effect sizes) analysis assessed differences between the two conditions., Results: The low-point classification group performed significantly slower in the active start (p<0.05). There were no differences in sprint time for the high- and mid-point groups. Mid-point players achieved greater peak accelerations for strokes two and three in the active start (p<0.05). Individual sprint performances varied substantially, ranging from 8% decrease to 14% increase in sprint time for the active start. Meaningful differences in peak accelerations were demonstrated for 23 out of the 25 players., Conclusions: Small amendments to test design can lead to significant differences in individual athlete performance. Traditional group analyses masked important individual responses to testing conditions. There is need to further consider representative test design, and individual analysis for monitoring physical and skill performance., (Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Purpose: Maximal acceleration from standstill has been identified as a key performance indicator in wheelchair rugby; however, the impact of classification and kinematic variables on performance has received limited attention. This study aimed to investigate kinematic variables during maximal acceleration, with level of activity limitation accounted for using sport-classification scores., Methods: Based on their sporting classification scores, which reflect combined trunk, arm, and hand function, 25 elite wheelchair rugby players were analyzed in high-, mid-, and low-point groups before completing five 5-m sprints from a stationary position. Inertial measurement units and video analysis were used to monitor key kinematic variables., Results: Significant differences in kinematic variables were evident across the classification groups, particularly for the first stroke-contact angle (1-way ANOVA F 2,122  = 51.5, P < .05) and first stroke time (F 2,124  = 18.3, P < .05). High-point players used a first stroke-contact angle that was closer to top dead center of the wheel than either other group, while also using a shorter overall stroke time than low-point players. A linear mixed-effects model was used to investigate how kinematic variables influenced performance, with results suggesting that increased release angles (ie, farther around the wheel) and decreased stroke angles resulted in larger peak accelerations. Further investigation revealed that these results are likely influenced by strong relationships for the high-point group, as there was often no clear trend evident for midpoint and low-point groups., Conclusion: Findings show that various propulsion approaches exist across classification groups, with this information potentially informing individual wheelchair setups and training programs.