Search Results (13)

This study aims to evaluate the concurrent validity and test–retest reliability of wheelchair racing performance metrics. Thirteen individuals without disabilities and experience in wheelchair racing were evaluated twice while performing maximal efforts on a racing wheelchair. Three wheelchair athletes were also assessed to compare their performance with novice participants. The wheelchair kinematics was estimated using an inertial motion unit (IMU) positioned on the frame and a light detection and ranging (Lidar) system. The propulsion cycle (PC) duration, acceleration, average speed, speed gains during acceleration, and speed loss during deceleration were estimated for the first PC and stable PCs. The test–retest reliability was generally moderate (0.50 ≤ ICC < 0.75) to good (0.75 ≤ ICC < 0.90), while few metrics showed poor reliability (ICC < 0.50). High to very high correlations were obtained between both systems for 10 out of 11 metrics (0.78–0.99). Wheelchair athletes performed better than novice participants. Our results suggest that integrated accelerometer data could be used to assess wheelchair speed characteristics over a short distance with a known passage time. Such fine-grain analyses using methods usable in the field could allow for data-informed training in novice and elite wheelchair racing athletes. Full article

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. Full article

This review reports on the use of sensors in wheelchair sports to monitor and analyze performance during match and training time. With rapid advancements in electronics and related technologies, understanding performance metrics in wheelchair sports is essential. We reviewed nine studies using various sensor types, including electric motors, inertial measurement units, miniaturized data loggers with magnetic reed switches, and smartphones with inbuilt accelerometers and gyroscopes, operating at frequencies from 8 Hz to 1200 Hz. These studies measured parameters such as angular and translational velocities, distance, number of starts/pushes, and other performance indicators in sports such as basketball, rugby, tennis, and racing. Despite differences in sport types and methodologies, most studies found sensor-derived data effective for assessment of performance. Future developments and research in this field should focus on multi-sensor systems that could provide real-time match analysis and deeper insights into performance metrics. Overall, sensor technologies show significant potential for improving wheelchair sport performance diagnostics, contributing to better athlete training and future wheelchair design, and enhancing competitive outcomes. This review emphasizes the need for continued innovation and standardization in applying sensor technologies in wheelchair sports. Full article

Exercise increases the serum level of interleukin-6 (IL-6), which in turn stimulates the production of various inflammatory cytokine antagonists, such as interleukin-1 receptor antagonist (IL-1ra). Individuals with cervical spinal cord injury (CSCI) are at high risk of inflammatory conditions. This study compared the effects of wheelchair half marathon on the immune system of male athletes with CSCI and those with thoracic/lumber spinal cord injury (SCI). Neutrophil count, IL-1ra, IL-6, and various endocrine parameters were measured before, immediately and 1 h after the race in five CSCI and six SCI who completed the wheelchair marathon race. The percentage of neutrophils was significantly higher in CSCI immediately and 1 h after the race, compared with the baseline, and significantly higher in SCI at 1 h after the race. IL-6 was significantly higher immediately and 1 h after the race in SCI, whereas no such changes were noted in IL-6 in CSCI. IL-1ra was significantly higher at 1 h after the race in both SCI and CSCI. The race was associated with an increase in IL-1ra in both CSCI and SCI. These findings suggest wheelchair half marathon race increases IL-1ra even under stable IL-6 status in male CSCI individuals, and that such post-race increase in IL-1ra is probably mediated through circulatory neutrophils. Full article

Long-term motor training can cause functional and structural changes in the human brain. Assessing how the training of specific movements affects specific parts of the neural circuitry is essential to understand better the underlying mechanisms of motor training-induced plasticity in the human brain. We report a single-case neuroimaging study that investigated functional and structural properties in a professional athlete of wheelchair racing. As wheelchair racing requires bilateral synchronization of upper limb movements, we hypothesized that functional and structural properties of interhemispheric interactions in the central motor system might differ between the professional athlete and controls. Functional and diffusion magnetic resonance imaging (fMRI and dMRI) data were obtained from a top Paralympian (P1) in wheelchair racing. With 23 years of wheelchair racing training starting at age eight, she holds an exceptional competitive record. Furthermore, fMRI and dMRI data were collected from three other paraplegic participants (P2-P4) with long-term wheelchair sports training other than wheelchair racing and 37 able-bodied control volunteers. Based on the fMRI data analyses, P1 showed activation in the bilateral precentral hand sections and greater functional connectivity between these sections during a right-hand unimanual task. In contrast, other paraplegic participants and controls showed activation in the contralateral hemisphere and deactivation in the ipsilateral hemisphere. Moreover, dMRI data analysis revealed that P1 exhibited significantly lower mean diffusivity along the transcallosal pathway connecting the bilateral precentral motor regions than control participants, which was not observed in the other paraplegic participants. These results suggest that long-term training with bilaterally synchronized upper-limb movements may promote bilateral recruitment of the precentral hand sections. Such recruitment may affect the structural circuitry involved in the interhemispheric interaction between the bilateral precentral regions. This study provides valuable evidence of the extreme adaptability of the human brain. Full article

The analysis of intra-cycle velocity profile of manual wheelchair (MWC) users has been used to highlight the significant role of trunk inertia in propulsion biomechanics. Maximal wheelchair linear velocity has previously been observed to be reached after the release of the handrims both during sports activities and daily life propulsion. This paper provides a combined analysis of linear velocity and trunk kinematics in elite wheelchair racing athletes during straight-line propulsion at stabilized speeds. MWC and trunk kinematics of eight athletes (level: 7 elite, 1 intermediate; classification: T54 (5), T53 (2) and T52 (1)) were monitored during 400 m races using inertial measurement units. An average propulsion cycle was computed for each athlete. The main finding of this article is the difference in propulsion patterns among the athletes, exhibiting either 1, 2 or 3 peaks in their velocity profile. A second peak in velocity is usually assumed to be caused by the inertia of the trunk. However, the presence of a second velocity peak among more severely impaired athletes with little to no trunk motion can either be associated to the inertia of the athletes’ arms or to their propulsion technique. Full article

This work proposes an augmented reality serious game (ARSG) for supporting individuals with motor disabilities while controlling robotic wheelchairs. A racing track was used as the game narrative; this included restriction areas, static and dynamic virtual objects, as well as obstacles and signs. To experience the game, a prior configuration of the environment, made through a smartphone or a computer, was required. Furthermore, a visualization tool was developed to exhibit user performance while using the ARSG. Two user studies were conducted with 10 and 20 participants, respectively, to compare (1) how different devices enable configuring the ARSG, and (2) different tracking capabilities, i.e., methods used to place virtual content on the real-world environment while the user interacts with the game and controls the wheelchair in the physical space: C1—motion tracking using cloud anchors; C2—offline motion tracking. Results suggest that configuring the environment with the computer is more efficient and accurate, in contrast to the smartphone, which is characterized as more engaging. In addition, condition C1 stood out as more accurate and robust, while condition C2 appeared to be easier to use. Full article

Manual wheelchair (MWC) users are exposed to whole-body vibrations (WBVs) during propulsion. Vibrations enter the MWC structure through the wheels’ hub, propagate according to the MWC dynamical response, and finally reach the user’s body by the footrest, seat, backrest, and handrims. Such exposure is likely to be detrimental to the user’s health and a source of discomfort and fatigue which could, in daily life, impact users’ social participation and performance in sports. To reduce WBV exposure, a solution relies on MWC dynamical response modelling and simulation, where the model could indeed be used to identify parameters that improve the MWC dynamic. As a result, it is necessary to first assess the MWC dynamical response. In this approach, experimental modal analyses were conducted on eleven MWCs, including daily and sport MWCs (tennis, basketball, and racing). Through this procedure, modal properties (i.e., modal frequencies, damping parameters, and modal shapes) were identified for each MWC part. The results pointed out that each MWC investigated, even within the same group, revealed specific vibration properties, underlining the difficulty of developing a single vibration-reducing system for all MWCs. Nevertheless, several common dynamical properties related to MWC comfort and design were identified. Full article

Wheelchair racing gloves are typically solid 3D structures held in a clenched fist which help to propel the chair by pushing the glove against a rotating rail which is attached to the wheel to drive the wheelchair forward. There has been a recent movement towards developing customisable gloves using 3D scanning technique, however, currently there are no commercial offerings which allow for product customisation without being prohibitively expensive. The aim of this project, therefore, was to develop a scalable method for producing customised wheelchair racing gloves in a cost-effective way. The generated 3D forms were 3D printed in a variety of infill densities and finished with a grip liner. These 3D printed gloves were compared in terms of fit and perception of performance, and for their mass, cost and energy/power cost. The 3D printed gloves provided a substantially reduced mass with only a minimal reduction in overall strength at a comparable cost to the solid equivalent. Full article

In this paper, an innovative system of propulsion inspired by a rowing gesture for manual wheelchairs is shown. The innovative system of propulsion, named Handwheelchair.q, can be applied to wheelchairs employed in everyday life and to sports wheelchairs for speed races, such as Handbike and Wheelchair racing. The general features of the innovative system of propulsion and the functional designs of the different solutions are described in detail. In addition, the design of the mechanism for the transmission of motion, employed in a second prototype, Handwheelchair.q02, is presented and analysed. Finally, the dynamic model of the Handwheelchair.q has been developed in order to obtain important results for the executive design of Handwheelchair.q. Full article

In wheelchair racing, the optimal pair of gloves, as well as knowledge of conditioning of glove-rim contact surfaces can have a significant impact on race performance. Extreme temperatures, humidity, wet or dry conditions can considerably influence not only the hand-rim friction coupling (effectiveness of the athlete’s push cycle) but also the risk of injuries, blisters or sore areas which in turn, can influence the endurance of the athlete across long distance events. This paper reports an experimental study of the effect of bio-mimicry surface textures as a supplement for heightening glove-rim coupling for dry and wet weather conditions. The paper also provides recommendations for the practical implementation of the study findings through a proposal for the design and development of a pair of bespoke gloves for a wheelchair racing athlete for initial prototyping and performance trials. Full article

The instrumentation of wheelchair racing chairs is currently limited by the influence of the athlete-wheelchair system mass and performance. Inertial measurement units (IMUs) provide a lightweight solution, and have demonstrated accurate kinematic monitoring of wheelchair ball sports. With the aim of investigating the capability of IMUs detecting contact and release timings, a study was performed on seven national level wheelchair racing athletes (T34 and T54 classifications). Athletes performed treadmill-based propulsion at speeds ranging between 19 km/h and 32 km/h, with the population sample enabling comparison between classification, propulsion speed, gender, age, glove type and wheel type. Contact and release timing points of each athlete were verified against measures obtained using video capture (100 Hz), which is considered a gold standard measure. IMUs identified contact timings for all athletes, however could not consistently identify release points for all athletes. Propulsion speed and gender were found to have minimal influence on the capacity to determine contact. Full article

A high prevalence of shoulder injuries exists across the wheelchair using populations. To maintain competitive longevity and optimise performance, athletes must employ techniques which pose minimal injury risk. A computational model was used to assess relationships between the magnitude of reaction moments at the shoulder with key propulsion characteristics, including; contact and release angles, hand speed at contact, and joint angles at contact. Subject-specific musculoskeletal models (mass, maximum isometric force) for two elite wheelchair racing athletes were derived, and driven through kinetic and kinematic data obtained using motion capture. Greater reaction moments (min 72.6 Nm, max: 1077.8 Nm) at the shoulder were correlated with hand velocity (7.2 m/s–9.3 m/s) at contact (|r| > 0.866, p < 0.013), push time (|r| > 0.866, p < 0.013), and kinematic positioning at contact (|r| > 0.784, p < 0.020). Variations between athlete reaction force at the pushrim and joint reaction moments demonstrate the importance of coupled kinematic and modelling analysis in prescribing technique adaptations. Full article