International Wheelchair Rugby Federation Research Articles

Optimising classification of proximal arm strength impairment in wheelchair rugby: A proof of concept study

ABSTRACT This study examined the relationship between proximal arm strength and mobility performance in wheelchair rugby (WR) athletes and examined whether a valid structure for classifying proximal arm strength impairment could be determined. Fifty-seven trained WR athletes with strength impaired arms and no trunk function performed six upper body isometric strength tests and three 10 m sprints in their rugby wheelchair. All strength measures correlated with 2 m and 10 m sprint times (r ≥ −0.43; p ≤ 0.0005) and were entered into k-means cluster analyses with 4-clusters (to mirror the current International Wheelchair Rugby Federation [IWRF] system) and 3-clusters. The 3-cluster structure provided a more valid structure than both the 4-cluster and existing IWRF system, as evidenced by clearer differences in strength (Effect sizes [ES] ≥ 1.0) and performance (ES ≥ 1.1) between adjacent clusters and stronger mean silhouette coefficient (0.64). Subsequently, the 3-cluster structure for classifying proximal arm strength impairment would result in less overlap between athletes from adjacent classes and reduce the likelihood of athletes being disadvantaged due to their impairment. This study demonstrated that the current battery of isometric strength tests and cluster analyses could facilitate the evidence-based development of classifying proximal arm strength impairment in WR.

Personalized Tests in Paralympic Athletes: Aerobic and Anaerobic Performance Profile of Elite Wheelchair Rugby Players.

In Paralympic sports, the goal of functional classifications is to minimize the impact of impairment on the outcome of the competition. The present cross-sectional study aimed to investigate aerobic and anaerobic personalized tests in Paralympic athletes and to correlate them with the classification of the international wheelchair rugby federation (IWRF). Sixteen elite players of the Italian wheelchair rugby team volunteered for the study. Aerobic (incremental test to exhaustion) and anaerobic (Wingate 30s all-out test, 5 and 10-meter sprint test, shuttle test, isometric test) sport-performance measurements were correlated singularly or grouped (Z scores) with the classification point. Moreover, a multivariate permutation-based ranking analysis investigated possible differences in the overall level of performance among the adjacent classified groups of players, considering the scores of each test. A statistically significant correlation between the performance parameters and the IWRF functional classification considering both aerobic and anaerobic personalized tests was detected (0.58 ≤ r ≤ 0.88; 0.0260 ≤ p ≤ 0.0001). The multivariate permutation-based ranking analysis showed differences only for the low-pointers versus mid-pointers (p = 0.0195) and high-pointers (p = 0.0075). Although single performance parameters correlated with athletes’ classification point, results of the multivariate permutation-based ranking analysis seem to suggest considering only the most significant anaerobic and sport-specific performance parameters among athletes. These should be combined with the physical assessment and the qualitative observation, which are already part of the classification process to improve its effectiveness.

Spinal Cord Injury Impairs Cardiovascular Capacity in Elite Wheelchair Rugby Athletes.

To examine differences in heart rate (HR) responses during international wheelchair rugby competition between athletes with and without a cervical spinal cord injury (SCI) and across standardized sport classifications. Observational study. The 2015 Parapan American Games wheelchair rugby competition. Forty-three male athletes (31 ± 8 years) with a cervical SCI (n = 32) or tetraequivalent impairment (non-SCI, n = 11). Average and peak HR (HRavg and HRpeak, respectively). To characterize HR responses in accordance with an athletes' International Wheelchair Rugby Federation (IWRF) classification, we separated athletes into 3 groups: group I (IWRF classification 0.5-1.5, n = 15); group II (IWRF classification 2.0, n = 15); and group III (IWRF classification 2.5-3.5, n = 13). Athletes with SCI had lower HRavg (111 ± 14 bpm vs 155 ± 13 bpm) and HRpeak (133 ± 12 bpm vs 178 ± 13 bpm) compared with non-SCI (both P < 0.001). Average HR was higher in group III than in I (136 ± 25 bpm vs 115 ± 20 bpm, P = 0.045); however, SCI athletes showed no difference in HRavg or HRpeak between groups. Within group III, SCI athletes had lower HRavg (115 ± 6 bpm vs 160 ± 8 bpm) and HRpeak (135 ± 11 bpm vs 183 ± 11 bpm) than non-SCI athletes (both P < 0.001). This study is the first to demonstrate attenuated HR responses during competition in SCI compared with non-SCI athletes, likely due to injury to spinal autonomic pathways. Among athletes with SCI, IWRF classification was not related to differences in HR. Specific assessment of autonomic function after SCI may be able to predict HR during competition and consideration of autonomic impairments may improve the classification process.

Analysis ofUSAWR Wheelmill VO2 Max Testing Between Classes

PURPOSE: Little is known about how elite level training can affect the Maximum Aerobic Capacity (Max VO2) testing for all functional classifications of national wheelchair rugby athletes. The primary purpose of this study was to review existing Max VO2 data between Higher Classification (HC) and Lower Classification (LC) players on the USA Wheelchair Rugby Team (USAWR). METHODS: Data was collected during the April training camp (camp1) and August training camp (camp2) at Lakeshore Foundation during the 2017 season. All athletes followed an individualized high intensity workout plan between camp1 and camp2. Athletes (n = 12) had to perform a graded VO2 max test on a unique Wheelmill ergometer during both camps to be included. Variables tested for significance included absolute VO2 (aVO2), relative VO2 (rVO2), Respiratory Exchange Ratio (RER), Heart Rate (HR), Ventilatory Equivalent (VE), and Rate of Perceived Exertion (RPE). International Wheelchair Rugby Federation classifications are set by functional ability starting at 0.5 and progress up in 0.5 increments to a max level of 3.5. For this study, classifications were grouped into those whose roles were primarily as a blocker (Class 0.5 – 1.5) and those whose roles were primarily ball handlers (class 2.0 – 3.5). RESULTS: Means for the whole team were tested for significant change between camp1 and camp2, and then between HC and LC using 2-tailed T-test (95% confidence interval). Despite whole team mean aVO2 and mean rVO2 was not significantly changed, whole team mean VE significantly increased from camp1 to camp2 (64.92 L/min + 9.5601, p=0.0146), as did RER (1.0750 + 0.0636, p=0.0387). Significant rVO2 Max changes occurred among LC athletes (17.9300 mL/kg/min + 1.1172, p=0.0246) and with aVO2 Max (1.5000 L/min + 0.0990, p=0.0346), but no significant changes occurred among HC group. CONCLUSION: Analysis results showed significant improvements in maximum achieved VE and RER variables between camp1 and camp2 in elite wheelchair rugby athletes. When separated into LC and HC groups, only LC showed significant improvements in rVO2 and aVO2. This could indicate that elite USAWR training methods are more effectively improving performance in athletes with lower classifications than in their higher classification counterparts.

Autonomic testing for prediction of competition performance in Paralympic athletes.

While we now appreciate that autonomic dysfunction can impact wheelchair rugby performance, this is currently not being assessed during classification, largely due to lack of a standardized and evidence-based strategy to assess autonomic function. Our aim, therefore, was to establish the optimal autonomic testing protocol that best predicts cardiovascular capacity during competition by comprehensively examining autonomic function in elite wheelchair rugby athletes with cervical SCI and thereby enhance the standardized classification. Twenty-six individuals with cervical SCI (C4-C8; AIS A, B, C) participated in this study during the 2015 Parapan American Games in Toronto, Canada. Clinic autonomic testing included: sympathetic skin responses, baseline hemodynamics, orthostatic challenge test, and cold-pressor tests. Further, we completed standard motor/sensory assessments and obtained each participants' International Wheelchair Rugby Federation classification. These clinic metrics were correlated to in-competition heart rate monitoring obtained during competition. The current study provides novel evidence that the change in systolic blood pressure during an orthostatic challenge test predicts approximately 50% of the in-competition peak heart rate (P<.001). Conversely, International Wheelchair Rugby Federation classification was poorly associated with in-competition peak heart rate (R2 =.204; P<.05). Autonomic testing provides deep insight regarding preserved autonomic control after SCI that is associated with performance in elite wheelchair rugby athletes. As such, incorporating assessments of cardiovascular capacity in classification will help to ensure a level playing field and may obviate the need for practices such as boosting to gain an advantage due to poor cardiovascular control.

Dimensions of achievement goal orientation and coping in South African wheelchair rugby players with quadriplegia

This study investigated the relationship between dispositional achievement goal orientation (task and ego) and coping ability in wheelchair rugby players with quadriplegia. The sample consisted of 16 (15 males and 1 female) players between the ages of 25 and 44 (M=33.7 years; SD=8.7) who were selected for South Africa's national training squad in preparation for the 2011 International Wheelchair Rugby Federation (IWRF) Asia-Oceania Championship. Players self-reported on their perception of success and athletic coping skills. The data were analysed for correlational associations between dimensions of achievement goal orientation and psychological skills associated with coping in sport. Findings revealed that players have both high task and fairly high ego orientation of which task orientation was significantly correlated with coping ability.

Activity profiles of elite wheelchair rugby players during competition.

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. 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). 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. 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.

Effect of team rank and player classification on activity profiles of elite wheelchair rugby players

The aim of the current study was to establish which indicators of mobility are associated with successful wheelchair rugby performance and determine whether these indicators differed across classification. Data were collected from 11 international teams during 30 matches (353 match observations) using a radio-frequency-based, indoor tracking system across two tournaments. Players (n = 111) were first grouped by team rank as determined by their International Wheelchair Rugby Federation (IWRF) world ranking (LOW, MID, HIGH) and then into one of four groups based on their IWRF classification: Group I (0.5), Group II (1.0–1.5), Group III (2.0–2.5) and Group IV (3.0–3.5). The volume of activity (relative distance and mean speed), peak speed and time spent within classification-specific arbitrary speed zones were calculated for each individual. Although no differences were identified in the volume of activity, playing time was significantly reduced in LOW (34:51 ± 8:35) compared to MID (48:54 ± 0:51) and HIGH (45:38 ± 9:53), which was further supported by the greater number of substitutions performed by LOW. HIGH achieved greater peak speeds (3.55 ± 0.40 m · sˉ1) than LOW (3.27 ± 0.42 m · sˉ1) and MID (3.45 ± 0.41 m · sˉ1). Peak speed was further shown to be classification-dependent (P ≤ 0.005), whereby HIGH Groups III and IV players achieved greater peak speeds than LOW and MID. The time spent performing high-intensity activities was also greater in HIGH compared to LOW and MID, whilst further influenced by classification (P ≤ 0.0005). To conclude, peak speed and the ability to perform a greater number of high-intensity activities were associated with successful performance in wheelchair rugby.

Improvement of the classification system for wheelchair rugby: athlete priorities.

A representative sample (N=302) of the wheelchair rugby population responded to a survey about the classification system based on prioritized items by International Wheelchair Rugby Federation members. Respondents stated, "The classification system is accurate but needs adjustments" (56%), "Any athlete with tetraequivalent impairment should be allowed to compete" (72%), "Athletes with cerebral palsy and other coordination impairments should be classified with a system different than the current one" (75%), and "The maximal value for trunk should be increased from 1.0 to 1.5" (67%). A minority stated, "Wheelchair rugby should only be open to spinal cord injury and other neurological conditions" (36%) and "There should be a 4.0 class" (33%). Results strongly indicated that athletes and stakeholders want adjustments to the classification system in two areas: a focus on evaluation of athletes with impairments other than loss of muscle power caused by spinal cord injury and changes in classification of trunk impairment.

Autonomic Function and Exercise Performance in Elite Athletes with Cervical Spinal Cord Injury

"Complete" cervical spinal cord injury (SCI) is commonly believed to cause the decentralization of spinal sympathetic circuits and a consequent inability to meet the hemodynamic demands of exercise. Recently, however, we have noticed that athletes with motor complete cervical SCI exhibit an exercise-induced tachycardia that appears to be at odds with the known effects of sympathetic decentralization. This study aimed to determine the physiological basis of this response and, in doing so, to investigate associations between autonomic function, International Wheelchair Rugby Federation (IWRF) classification, and indices of exercise performance in highly trained athletes. Seven Paralympic wheelchair rugby players with motor complete cervical SCI were firstly classified according to IWRF classification, then assessed for autonomic function (sympathetic skin response [SSR]) and cardiovascular function (systolic blood pressure in response to sit-up tilt). Next, HRpeak and distance covered during a field-based maximal 4-min push were measured. Finally, peak oxygen uptake (VO2peak) and HRpeak during laboratory-based maximal incremental arm-crank exercise were measured. All athletes demonstrated intact SSR (2.7 ± 1.2 responses from five stimulations), little or no change in systolic blood pressure in response to sit-up tilt (-22 ± 16 mm Hg), and exercise-induced tachycardia (HRpeak = 152 ± 20 bpm). SSR was significantly correlated with HRpeak in the field, 4-min push distance, and VO2peak (all ρ ≥ 0.946), whereas current IWRF classification was not. All participants exhibited partial preservation of descending sympathetic control. We also found that the degree of remaining SSR, but not IWRF classification, was strongly correlated with indices of exercise performance. The findings suggest that the degree of remaining sympathetic control is an important determinant of exercise performance in athletes with cervical SCI.

Aerobic, Anaerobic, and Skill Performance With Regard to Classification in Wheelchair Rugby Athletes

The purpose of the study was to examine the sport-specific performance of wheelchair rugby players with regard to their classification. A group of 30 male athletes from the Polish Wheelchair Rugby League participated in the study. The seven International Wheelchair Rugby Federation classes were collapsed into four groups. Standardized measures of aerobic, anaerobic, and skill performance were examined to identify performance differences among the four groups. Major findings were that most differences were between Group I players and all others and that anaerobic performance was the most sensitive to classification differences. Another important finding was that for all other groups, with one exception, adjacent groups did not differ in anaerobic, aerobic, and sport-specific skill performance. The results of this study demonstrate the need to investigate other performance measures that will help in evaluating the current wheelchair rugby classification system.

An Examination of the International Wheelchair Rugby Federation Classification System Utilizing Parameters of Offensive Game Efficiency

The purpose of the study was to examine the offensive game efficiency of elite wheelchair rugby players with regard to their International Wheelchair Rugby Federation (IWRF) classification. Male athletes (105) representing 12 European nations competing at the 2005 European Wheelchair Rugby Championships took part in this study. The primary recording instrument was the Game Efficiency Sheet (GES), an instrument designed to objectively record parameters of wheelchair rugby efficiency such as points scored, steals, turnovers, balls caught (%), and balls passed (%). Kruskal-Wallis between groups analyses identified significant differences among the lower classification groups (0.5-2.0) and between the lower and higher classification (2.5-3.5) groups. Further research is needed in identifying game efficiency differences in higher class groups.

Classifiers and social control in wheelchair rugby.

The purpose of this study was to examine the features of wheelchair rugby classifiers in order to maintain social control in wheelchair rugby. The examination centered on the theme-resources used by classifiers to maintain the authority of International Wheelchair Rugby Federation (IWRF). Data were collected using participant observation methodology at national and international wheelchair rugby championships and a survey of the 14 IWRF authorized classifiers. The results of this study identified five essential features of IWRF classifiers. In particular, they need to have a background in medicine or physical therapy. In addition, IWRF classifiers use their medical and sporting knowledge and experience to control the wheelchair rugby classification process and to maintain fairness of competition. The results of this study may help to train Taiwanese professionals with medical or sporting backgrounds to become international classifiers and also to develop appropriate training programs for national classifiers.