Search

The purpose of this study was to describe and explore an inertial measurement unit-based method to analyse drag forces and external power loss in wheelchair tennis, using standardised coast-down and 10 m sprint tests. Drag forces and power output were explored among different wheelchair-athlete combinations and playing conditions (tyre pressure, court-surface). Eight highly trained wheelchair tennis players participated in this study. Three inertial measurement units (IMUs) were placed on the frame and axes of the wheels of their wheelchair. All players completed a set of three standardised coast-down trials and two 10 m sprints with different tyre pressures on hardcourt surface. One athlete completed additional tests on a clay/grass tennis-court. Coast-down based drag forces of 4.8–7.2 N and an external power loss of 9.6–14.4 W at a theoretical speed of 2 m/s were measured on hardcourt surface. A higher tyre pressure led to lower drag forces during coast-down tests on hardcourt surface (Fr (4) = 10.7, p = 0.03). For the single athlete, there was an external power loss of 10.4, 15.6 and 49.4 W, respectively, for the hardcourt, clay and grass. The current prediction of power output was implemented during coast-down testing; unfortunately, the power prediction during 10 m sprints was difficult to accomplish. [ABSTRACT FROM AUTHOR]

Purpose: To examine the efficacy of per-cooling via ice slurry ingestion (ICE) in wheelchair tennis players exercising in the heat. Method: Eight wheelchair tennis players undertook sprints (4 sets of 10 × 5 s over 40 min) in a hot environment (∼32 °C), interspersed by 3 boluses of 2.67 g·kg (6.8 g·kg total) ICE or drinking temperate water (control condition). Athletes performed an on-court test of repeated sprint ability (20 × 20 m) in temperate conditions immediately before and 20 minutes after the heat exposure, and time to complete each sprint as well as intermediate times were recorded. Gastrointestinal and weighted mean skin and forehead temperatures were collected throughout the heat exposure, as were thermal sensation, heart rate, and blood lactate concentration. Sweat rate was calculated from body mass changes and fluid/ice intakes. Results: Compared with the control condition, ICE resulted in a significantly lower gastrointestinal temperature (95% CI, 0.11–0.17 °C; P <.001), forehead temperature (0.58–1.06 °C; P <.001), thermal sensation (0.07–0.50 units; P =.017), and sweat rate (0.06–0.46 L·h−1; P =.017). Skin temperature, heart rate, and blood lactate concentration were not significantly different between conditions (P ≥.598). There was no overall change preheating to postheating (P ≥.114) or an effect of condition (P ≥.251) on repeated sprint times. Conclusions: ICE is effective at lowering objective and subjective thermal strain when consumed between sets of repeated wheelchair sprints in the heat. However, ICE has no effect on on-court repeated 20-m sprint performance. [ABSTRACT FROM AUTHOR]

Purpose: To compare the effects of typical competition versus high-intensity intermittent warm-up (WU) on thermoregulatory responses and repeated sprint performance during wheelchair rugby game play. Methods: An intermittent sprint protocol (ISP) simulating the demands of wheelchair rugby was performed by male wheelchair rugby players (7 with cervical spinal cord injury [SCI] and 8 without SCI) following 2 WU protocols. These included a typical competition WU (control) and a WU consisting of high-intensity efforts (INT). Core temperature (Tcore), thermal sensation, and thermal comfort were recorded. Wheelchair performance variables associated to power, speed, and fatigue were also calculated. Results: During the WU, Tcore was similar between conditions for both groups. During the ISP, a higher Tcore was found for SCI compared to NON-SCI (38.1 [0.3] vs 37.7 [0.3] °C: P =.036, d = 0.75), and the SCI group experienced a higher peak Tcore for INT compared with control (39.0 [0.4] vs 38.6 [0.6] °C; P =.004). Peak Tcore occurred later in the ISP for players with SCI (96 [5.8] vs 48 [2.7] min; P <.001). All players reported a higher thermal sensation and thermal comfort following INT (P <.001), with no differences between conditions throughout the ISP. No significant differences were found in wheelchair performance variables during the ISP between conditions (P ≥.143). Conclusions: The high-INT WU increased thermal strain in the SCI group during the ISP, potentially due to increased metabolic heat production and impaired thermoregulation, while not impacting on repeated sprint performance. It may be advisable to limit high-INT bouts during a WU in players with SCI to mitigate issues related to hyperthermia in subsequent performance. [ABSTRACT FROM AUTHOR]

Quantifying measures of physical loading has been an essential part of performance monitoring within elite able-bodied sport, facilitated through advancing innovative technology. In wheelchair court sports (WCS) the inter-individual variability of physical impairments in the athletes increases the necessity for accurate load and performance measurements, while at the same time standard load monitoring methods (e.g. heart-rate) often fail in this group and dedicated WCS performance measurement methods are scarce. The objective of this review was to provide practitioners and researchers with an overview and recommendations to underpin the selection of suitable technologies for a variety of load and performance monitoring purposes specific to WCS. This review explored the different technologies that have been used for load and performance monitoring in WCS. During structured field testing, magnetic switch-based devices, optical encoders and laser systems have all been used to monitor linear aspects of performance. However, movement in WCS is multidirectional, hence accelerations, decelerations and rotational performance and their impact on physiological responses and determination of skill level, is also of interest. Subsequently both for structured field testing as well as match-play and training, inertial measurement units mounted on wheels and frame have emerged as an accurate and practical option for quantifying linear and non-linear movements. In conclusion, each method has its place in load and performance measurement, yet inertial sensors seem most versatile and accurate. However, to add context to load and performance metrics, position-based acquisition devices such as automated image-based processing or local positioning systems are required. Highlights Objective measures of wheelchair mobility performance are paramount in wheelchair court sport support, since they enable quantification of workload across athletes of all classifications and in structured field testing, training and match play settings. Given the variety of methods for load and performance monitoring in wheelchair court sports, this review: identified and examined the technology available; provides meaningful insights and decision guidelines; describes applicability for different goals; and proposes practical recommendations for researchers and sports professionals. Wheelchair mounted inertial sensors are most reliable and versatile for measuring wheelchair mobility performance and estimates of workload, yet a combination with local position measurement via indoor tracking or image-based processing could be useful to add context. For wheelchair athletes bound to a wheelchair for daily use, workload monitoring on a regular basis, both on- and off-court, is crucial to avoid overuse injuries. Alternatively, in athletes with lower severity impairments often lack frequent exposure to optimal and progressive loading, reducing the likelihood of positive physiological adaptations. [ABSTRACT FROM AUTHOR]

Purpose: To determine the effect of trunk and arm impairments on physical and technical performance during wheelchair rugby (WR) competition. Methods: Thirty-one highly trained WR players grouped according to their trunk (no trunk [NT]; some trunk [T] function) and arm impairments (poor, moderate, and good arm function) participated in 5 WR matches. Players' physical (wheelchair mobility) and technical (ball handling) activities were analyzed using an indoor tracking system and video analysis, respectively. Results: Trunk impairment explained some of the variance in physical (10.6–23.5%) and technical (16.2–33.0%) performance. T covered more distance, had more possession, scored more goals, and received and made more passes yet spent less time at low speeds and performed fewer inbounds than NT (≤.05). Arm impairment explained some of the variance in all physical (16.7–47.0%) and the majority of technical (13.1–53.3%) performance measures. Moderate and good arm function covered more distance, reached higher peak speeds, spent more time in higher speed zones, scored more goals, had more possession, and received and made more passes, with a higher percentage of 1-handed and long passes, than poor arm function. Good arm function also received more passes and made a higher percentage of 1-handed passes and defensive blocks than moderate arm function (P ≤.05). Conclusions: Arm impairment affects a greater number of physical and technical measures of performance specific to WR than trunk impairment during competition. Having active finger function (good arm function) yielded no further improvements in physical performance but positively influenced a small number of technical skills. [ABSTRACT FROM AUTHOR]

Purpose: To examine the effects of different small-sided games (SSGs) on physical and technical aspects of performance in wheelchair basketball (WB) players. Design: Observational cohort study. Methods: Fifteen highly trained WB players participated in a single 5v5 (24-s shot clock) match and three 3v3 SSGs (18-s shot clock) on a (1) full court, (2) half-court, and (3) modified-length court. During all formats, players’ activity profiles were monitored using an indoor tracking system and inertial measurement units. Physiological responses were monitored via heart rate and rating of perceived exertion. Technical performance, that is, ball handling, was monitored using video analysis. Repeated-measures analysis of variance and effect sizes (ESs) were calculated to determine the statistical significance and magnitude of any differences between game formats. Results: Players covered less distance and reached lower peak speeds during half-court (P ≤.0005; ES ≥ very large) compared with all other formats. Greater distances were covered, and more time was spent performing moderate- and high-speed activity (P ≤.008; ES ≥ moderate) during full court compared with all other formats. Game format had little bearing on physiological responses, and the only differences in technical performance observed were in relation to 5v5. Players spent more time in possession, took more shots, and performed more rebounds in all 3v3 formats compared with 5v5 (P ≤.028; ES ≥ moderate). Conclusions: Court dimensions affect the activity profiles of WB players during 3v3 SSGs yet had little bearing on technical performance when time pressures (shot clocks) were constant. These findings have important implications for coaches to understand which SSG format may be most suitable for physically and technically preparing WB players. [ABSTRACT FROM AUTHOR]

Purpose: To examine the speed profiles of elite wheelchair rugby (WCR) players during game-simulation training drills of differing player number and shot-clock regulations. A secondary aim was to determine whether the profiles were further influenced by player classification. Methods: Eight elite WCR players (low-point n = 3, high-point n = 5) were monitored using a radio-frequency-based indoor tracking system during training sessions over a 5-mo period. Speed profiles were collected for 3 modified game-simulation drills--3-versus-3 drills (n = 8 observations), 30-s shot clock (n = 24 observations), and 15-s shot clock (n = 16 observations)--and were compared with regular game-simulation drills (4 vs 4, 40-s shot clock; n = 16 observations). Measures included mean and peak speed; exercise-intensity ratios, defined as the ratio of time spent performing at high and low speeds; and the number of high-speed activities performed. Results: Compared with regular game-simulation drills, 3-versus-3 drills elicited a moderate increase in mean speed (6.3%; effect size [ES] = 0.7) and the number of high-speed activities performed (44.1%; ES = 1.1). Minimal changes in speed profiles were observed during the 30-s shot clock, although moderate to large increases in all measures were observed during the 15-s shot-clock drills. Classification-specific differences were further identified, with increased activity observed for high-point players during the 3-versus-3 drill and for low-point players during the 15-s shot clock. Conclusion: By reducing the number of players on court and the shot clock to 15 s, coaches can significantly increase elite WCR players' speed profiles during game-simulation drills. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the speed profiles of individual training modes in comparison with wheelchair rugby (WCR) competition across player classifications. Methods: Speed profiles of 15 international WCR players were determined using a radio-frequency-based indoor tracking system. Mean and peak speed (m/s), work:rest ratios, and the relative time spent in (%) and number of high-speed activities performed were measured across training sessions (n = 464) and international competition (n = 34). Training was classified into 1 of 4 modes: conditioning (n = 71), skill-based (n = 133), game-related (n = 151), and game-simulation drills (n = 109). Game-simulation drills were further categorized by the structured duration, which were 3-min game clock (n = 44), 8-min game clock (n = 39), and 10-min running clock (n = 26). Players were grouped by their International Wheelchair Rugby Federation classification as either low-point (≤1.5; n = 8) or high-point players (≥2.0; n = 7). Results: Conditioning drills were shown to exceed the demands of competition, irrespective of classification (P ≤ .005; effect size [ES] = 0.6-2.0). Skill-based and game-related drills underrepresented the speed profiles of competition (P ≤ .005; ES = 0.5-1.1). Mean speed and work:rest ratios were significantly lower during 3- and 8-min game-simulation drills in relation to competition (P ≤ .039; ES = 0.5-0.7). However, no significant differences were identified between the 10-min running clock and competition. Conclusions: Although game-simulation drills provided the closest representation of competition, the structured duration appeared important since the 10-min running clock increased training specificity. Coaches can therefore modify the desired training response by making subtle changes to the format of game-simulation drills. [ABSTRACT FROM AUTHOR]

This paper demonstrates how a qualitative methodology can be used to gain novel insights into the demands of wheelchair racing and the impact of particular racing chair configurations on optimal sport performance via engagement with expert users (wheelchair racers, coaches, and manufacturers). We specifically explore how expert users understand how wheels, tires, and bearings impact sport performance and how they engage, implement, or reject evidence-based research pertaining to these components. We identify areas where participants perceive there to be an immediate need for more research especially pertaining to the ability to make individualized recommendations for athletes. The findings from this project speak to the value of a qualitative research design for capturing the embodied knowledge of expert users and also make suggestions for "next step" projects pertaining to wheels, tires, and bearings drawn directly from the comments of participants. [ABSTRACT FROM AUTHOR]

A fundamental aspect of classification systems in Paralympic sport is having valid and reliable measures of impairment. However, minimal consensus exists for assessing impaired strength, coordination and range of motion. This review aimed to systematically identify measures of upper body strength, coordination and range of motion impairments that meet the requirements for use in evidence-based classification systems in wheelchair sports. Three electronic databases were searched from 2003 until 31 August 2019 for studies that assessed upper body function of participants and used a measurement tool that assessed strength, coordination or range of motion. The body of evidence for each identified measure was appraised using the Grading of Recommendations Assessment, Development and Evaluation framework. Twenty-three studies were included: ten measured strength and coordination, and six measured range of motion. There was "moderate" confidence in using isometric strength for assessing strength impairment. Tapping tasks for the assessment of coordination impairment received a "low" confidence rating. All other identified measures of coordination and range of motion impairment received a "very low" confidence rating. Several potential measures were identified for assessing upper body strength, coordination and range of motion impairments. Further research is warranted to investigate their use for classification in Paralympic wheelchair sports. [ABSTRACT FROM AUTHOR]

Purpose: To quantify the activity profiles of elite wheelchair rugby (WCR) players and establish classification-specific arbitrary speed zones. In addition, indicators of fatigue during full matches were explored. Methods: Seventy-five elite WCR players from 11 national teams were monitored using a radio-frequency-based, indoor tracking system across 2 international tournaments. Players who participated in complete quarters (n = 75) and full matches (n = 25) were included and grouped by their International Wheelchair Rugby Federation functional classification: groups I (0.5), II (1.0–1.5), III (2.0–2.5), and IV (3.0–3.5). Results: During a typical quarter, significant increases in total distance (m), relative distance (m/min), and mean speed (m/s) were associated with an increase in classification group (P < .001), with the exception of groups III and IV. However, group IV players achieved significantly higher peak speeds (3.82 ± 0.31 m/s) than groups I (2.99 ± 0.28 m/s), II (3.44 ± 0.26 m/s), and III (3.67 ± 0.32 m/s). Groups I and II differed significantly in match intensity during very-low/low-speed zones and the number of high-intensity activities in comparison with groups III and IV (P < .001). Full-match analysis revealed that activity profiles did not differ significantly between quarters. Conclusions: Notable differences in the volume of activity were displayed across the functional classification groups. However, the specific on-court requirements of defensive (I and II) and offensive (III and IV) match roles appeared to influence the intensity of match activities, and consequently training prescription should be structured accordingly. [ABSTRACT FROM AUTHOR]

Wheelchair tennis (WT) propulsion is uniquely characterized by the requirement for racket holding coupled with effective hand-rim contact. Thus, investigations involving strategies to enhance chair mobility skills are merited. The aim was to examine the effects of organized practice on WT match play responses and the impact of racket holding during practice. Following physiological profiling involving graded and peak exercise testing, 16 able-bodied (AB) participants performed bouts of WT match play interspersed with practice involving wheelchair mobility drills completed with (R) or without (NR) a tennis racket. A data logger recorded distance and speed. Self-efficacy was reported. Significant main effects for match revealed higher post-practice overall and forwards distances (p < 0.05), peak (p < 0.005) and average (p < 0.05) speeds and self-efficacy (SE) (p = 0.001) were attained. During practice, lower distances and speeds were achieved with R, with a lower physiological cost than NR. Practice increases court movement and SE with no associated increases in physiological cost. Changes represent enhanced court mobility. Differences between practice characteristics provide options for skill development and optimization of health outcomes. Wheelchair tennis participation is likely to confer positive health effects in those with a disability or physical impairment. As chair propulsion combined with racket holding represents a complex skill challenge, novices may find the sport challenging to play. Tennis-specific mobility drills improve confidence and chair propulsion skill with likely crossover into tennis match play competence and ability. [ABSTRACT FROM AUTHOR]

Handcycling performance is dependent on the physiological economy of the athlete; however, handbike configuration and the biomechanical interaction between the two are also vital. The purpose of this study was to examine the effect of crank length manipulations on physiological and biomechanical aspects of recumbent handcycling performance in highly trained recumbent handcyclists at a constant linear handgrip speed and sport‐specific intensity. Nine competitive handcyclists completed a 3‐minute trial in an adjustable recumbent handbike in four crank length settings (150, 160, 170 & 180 mm) at 70% peak power output. Handgrip speed was controlled (1.6 m·s−1) across trials with cadences ranging from 102 to 85 rpm. Physiological economy, heart rate, and ratings of perceived exertion were monitored in all trials. Handcycling kinetics were quantified using an SRM (Schoberer Rad Messtechnik) powermeter, and upper limb kinematics were determined using a 10‐camera VICON motion capture system. Physiological responses were not significantly affected by crank length. However, greater torque was generated (P <.0005) and peak torque occurred earlier during the push and pull phase (P ≤.001) in longer cranks. Statistical parametric mapping revealed that the timing and orientation of shoulder flexion, shoulder abduction, and elbow extension were significantly altered in different crank lengths. Despite the biomechanical adaptations, these findings suggest that at constant handgrip speeds (and varying cadence) highly trained handcyclists may select crank lengths between 150 and 180 mm without affecting their physiological performance. Until further research, factors such as anthropometrics, comfort, and self‐selected cadence should be used to facilitate crank length selection in recumbent handcyclists. [ABSTRACT FROM AUTHOR]

Handcycling is a mode of mobility, and sport format within Para‐cycling, for those with a lower limb impairment. The exercise modality has been researched extensively in the rehabilitation setting. However, there is an emerging body of evidence detailing the physiological responses to handcycling in the competitive sport domain. Competitive handcyclists utilize equipment that is vastly disparate to that used for rehabilitation or recreation. Furthermore, the transferability of findings from early handcycling research to current international athletes regarding physiological profiles is severely limited. This narrative review aims to map the landscape within handcycling research and document the growing interest at the elite end of the exercise spectrum. From 58 experimental/case studies and four doctoral theses, we provide accounts of the aerobic capacity of handcyclists and the influence training status plays; present research regarding the physiological responses to handcycling performance, including tests of sprint performance; and discuss the finite information on handcyclists' training habits and efficacy of bespoke interventions. Furthermore, given the wide variety of protocols employed and participants recruited previously, we present considerations for the interpretation of existing research and recommendations for future work, all with a focus on competitive sport. The majority of studies (n = 21) reported aerobic capacity, detailing peak rates of oxygen uptake and power output, with values >3.0 L min−1 and 240 W shown in trained, male H3‐H4 classification athletes. Knowledge, though, is lacking for other classifications and female athletes. Similarly, little research is available concerning sprint performance with only one from eight studies recruiting athletes with an impairment. [ABSTRACT FROM AUTHOR]

The purpose of the current study was to determine the validity and reliability of an inertial sensor for assessing speed specific to athletes competing in the wheelchair court sports (basketball, rugby, and tennis). A wireless inertial sensor was attached to the axle of a sports wheelchair. Over two separate sessions, the sensor was tested across a range of treadmill speeds reflective of the court sports (1.0 to 6.0 m/s). At each test speed, ten 10-second trials were recorded and were compared with the treadmill (criterion). A further session explored the dynamic validity and reliability of the sensor during a sprinting task on a wheelchair ergometer compared with high-speed video (criterion). During session one, the sensor marginally overestimated speed, whereas during session two these speeds were underestimated slightly. However, systematic bias and absolute random errors never exceeded 0.058 m/s and 0.086 m/s, respectively, across both sessions. The sensor was also shown to be a reliable device with coefficients of variation (% CV) never exceeding 0.9 at any speed. During maximal sprinting, the sensor also provided a valid representation of the peak speeds reached (1.6% CV). Slight random errors in timing led to larger random errors in the detection of deceleration values. The results of this investigation have demonstrated that an inertial sensor developed for sports wheelchair applications provided a valid and reliable assessment of the speeds typically experienced by wheelchair athletes. As such, this device will be a valuable monitoring tool for assessing aspects of linear wheelchair performance. [ABSTRACT FROM AUTHOR]