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

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1 Research Quarterly for Exercise and Sport ISSN: (Print) (Online) Journal homepage: Aerobic, Anaerobic, and Skill Performance With Regard to Classification in Wheelchair Rugby Athletes Natalia Morgulec-Adamowicz, Andrzej Kosmol, Bartosz Molik, Abu B. Yilla & James J. Laskin To cite this article: Natalia Morgulec-Adamowicz, Andrzej Kosmol, Bartosz Molik, Abu B. Yilla & James J. Laskin (2011) Aerobic, Anaerobic, and Skill Performance With Regard to Classification in Wheelchair Rugby Athletes, Research Quarterly for Exercise and Sport, 82:1, 61-69, DOI: / To link to this article: Published online: 23 Jan Submit your article to this journal Article views: 215 View related articles Citing articles: 1 View citing articles Full Terms & Conditions of access and use can be found at Download by: [Mansfield University] Date: 12 January 2016, At: 11:48

2 Morgulec-Adamowicz, Kosmol, Molik, Yilla, Physiology and Laskin Research Quarterly for Exercise and Sport 2011 by the American Alliance for Health, Physical Education, Recreation and Dance Vol. 82, No. 1, pp Aerobic, Anaerobic, and Skill Performance With Regard to Classification in Wheelchair Rugby Athletes Natalia Morgulec-Adamowicz, Andrzej Kosmol, Bartosz Molik, Abu B. Yilla, and James J. Laskin 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. Key words: disability sport, peak oxygen consumption, quadriplegia, Wingate Anaerobic Test The purpose of classification is to ensure fairness and make competition more equitable among athletes with various functional abilities and disability types. To ensure fair competition in wheelchair rugby, players are classed into one of seven groups (from 0.5 to 3.5 points) depending on their level of disability (International Wheelchair Rugby Federation [IWRF], 1999). The higher the class, the higher the athlete s functional level. To ensure team balance in wheelchair rugby, the total value of Submitted: March 12, 2009 Accepted: November 21, 2009 Natalia Morgulec-Adamowicz is with the Department of Adapted Physical Activity at the Józef Piłsudski University of Physical Education. Andrzej Kosmol and Bartosz Molik are with the Department of Sports for Individuals with Disabilities at the Józef Piłsudski University of Physical Education. Abu B. Yilla is with the Department of Kinesiology at the University of Texas Arlington. James J. Laskin is with the School of Physical Therapy and Rehabilitation Science at the University of Montana. all players on each team cannot exceed eight points. This ensures that the athletes on the court at any one time will represent a mix of functional levels. Individuals with quadriplegia developed wheelchair rugby as the quadriplegic equivalent to wheelchair basketball (Dimsdale & Beck, 1988). The IWRF Classifier s Manual governs classification (IWRF, 2008). Currently, three components are used to determine players classification: (a) the Bench Test, composed of muscle tests, trunk tests assessing abdominal, back, pelvis, and lower extremity function in all planes and various situations and hand tests; (b) the Functional Movement Test, which evaluates sport-specific tasks and activities (pushing, turning, stopping, starting, changing directions, holding the chair against resistance, dribbling, passing, catching, retrieving the ball from the floor, rimming, and transferring) in a noncompetitive environment; and (c) Observations On-Court, consisting of observing an athlete in various situations on the court, during warm-up, training, and competition. Classifiers also observe the athlete off court while working with equipment such as tape, gloves, water bottles, tools, and binders (IWRF, 2008). This system represents a sport-specific classification approach based on medical, functional, and observational criteria. Therefore, the wheelchair rugby classification system is designed to RQES: March

3 ensure that winning or losing an event depends on talent, training, skill, fitness, and motivation rather than unevenness of disability-related variables among competitors (Vanlandewijck & Chappel, 1996). Several investigators have agreed that sport classification for individuals with disabilities needs to be scientifically examined to determine the effects of impairment on the athlete s performance (Brasile, 1990; DePauw, & Gavron, 1995; Higgs, Babstock, Buck, Parsons, & Brewer, 1990; McCann, 2003, 2006; Sherrill, 1999; Strohkendl, 2001, 2004; Tweedy, 2003). To date, only a few unpublished studies have examined the wheelchair rugby classification system (Altman, Hart, & Parkinson, 2006; Hart, 2006; Malone, Collins, & Orr, 2006; Molik, Morgulec, Bebenek, & Kosmol, 2006; Morgulec, Kosmol, & Molik, 2006; Schreiner, 2006; Wu, 2001). Most of these studies, however, were limited to issues of general wheelchair rugby classification principles (Hart; Wu) and procedures (Altman et al.; Schreiner). Some researchers attempted to analyze athletic performance with regard to classification in wheelchair rugby (Malone et al.; Molik et al.; Morgulec et al.), but thus far the results have been inconsistent. Aerobic Performance Wheelchair rugby combines short, intense exercise bouts over an extended playing time; thus, it requires aerobic as well as anaerobic capacity (Coutts, Reaburn, & Abt, 2003). Many studies have investigated the aerobic capacity in active men with quadriplegia (Bhambhani et al., 1995; Campbell, Williams, & Lakomy, 2002; Dallmeijer, Hopman, Angenot, & Van der Woude, 1997; Eriksson, Löfström, & Ekblom, 1988; Goosey-Tolfrey, Castle, & Webborn, 2006; Hopman, Dallmeijer, Snoek, & Van der Woude, 1996; Janssen, Dallmeijer, Veeger, & Van der Woude, 2002; Janssen, Van Oers, Hollander, Veeger, & Van der Woude, 1993; Valent et al., 2007). Most authors (Bhambhani, 2002; Eggers et al., 2001; Figoni, 1993; Hopman et al., 1996) agreed that peak oxygen consumption (VO 2 peak) is reduced for individuals with quadriplegia due to factors specific to the condition, such as reduced muscle mass and an impaired sympathetic nervous system. In general, it has been demonstrated that VO 2 peak is inversely related to the lesion levels in individuals with spinal cord injury (SCI; Coutts, Rhodes, & McKenzie, 1983; Eriksson et al., 1988; Janssen et al., 1993, 2002). In a review of several studies on athletes with SCI, Bhambhani (2002) concluded there was considerable overlap in peak aerobic performance among different classification levels across sports in individuals with quadriplegia and paraplegia. Anaerobic Performance Many studies attempted to examine the anaerobic performance of individuals with quadriplegia by using a wheelchair ergometer (WCE) or an arm crank ergometer (ACE) as the exercise mode (Goosey-Tolfrey et al., 2006; Janssen et al., 1993; Morgulec, Kosmol, Vanlandewijck, & Hübner-Wozniak, 2005; Morgulec et al., 2006; Van der Woude, Bakker, Elkhuizen, Veeger & Gwinn, 1997). Janssen et al. (2002) demonstrated that maximal power outputs during ACE were higher than WCE; thus, the testing mode must be considered when evaluating the literature. Therefore, results in studies investigating anaerobic performance of individuals with quadriplegia should include the experimental setup (WCE or ACE) and protocol (resistance) used. Previous studies reported that lesion level is one of the most limiting factors for an increase in anaerobic capacity in the SCI population (Hutzler, Ochana, Bolotin, & Kalina 1998; Janssen et al., 2002; Morgulec et al., 2005). Morgulec et al. (2006) used the Wingate arm ergometer test to examine anaerobic performance in wheelchair rugby players with regard to their classification. It was postulated that the lack of significant differences in anaerobic performance between point players and point players, and point players and point players may suggest a need to reexamine the IWRF classification system. Skill Performance Few studies have been published related to skill performance in wheelchair rugby players. Malone et al. (2006) suggested that the wheelchair rugby player classification system adequately divides athletes based on functional ability related to the sport. However, the results of that study indicated significant correlation between player classification and the five skill tests (20-m sprint, endurance sprint, up and back, passing, and slalom); the test validity and reliability were not examined. In the present study, the Beck Battery of Quad Rugby Skill Tests was used as a reliable and valid instrument for examining sport-specific skills (Yilla & Sherrill, 1998). Higgs et al. (1990) suggested there should be statistically significant performance differences between classes. Thus, the relationship between players classification and their sport-specific performance should be measurable. Wheelchair rugby is a contact game composed of many skills such as picking, blocking, passing, or wheelchair maneuverability, which depend on strength, speed, endurance, coordination, and flexibility. Strohkendl (2001) stated that only the athlete s physical potential should be the subject of classification. Based on this assumption the athletes performance (aerobic, anaerobic, and sportspecific skills) should be related to classification. Therefore, the purpose of this study was to examine the wheelchair rugby players performance with regard to their classification. The research objective was to identify differences in aerobic, anaerobic, and sport-specific skill performance among the classification groups. We 62 RQES: March 2011

4 hypothesized that the sport-specific performance of wheelchair rugby players would depend on the player s classification level. Method Participants A group of 30 male athletes from the Polish Wheelchair Rugby League took part in this study. Athletes were classified according to the IWRF Player Classification System (IWRF, 1999). Due to the relatively small sample size, participants were divided into four groups: Group I, 0.5-point players (n = 7); Group II, 1- and 1.5-point players (n = 9); Group III, 2- and 2.5-point players (n = 6); and Group IV, 3- and 3.5-point players (n = 8). Participants demographic information (age, height, body mass, time since injury, and wheelchair rugby experience) is presented in Table 1. All athletes had a similar training status of two sessions (2 3 hr) per week. Each participant provided written informed consent, and the Ethics Committee of the University of Physical Education in Warsaw approved the study. Instrumentation Body mass was measured using a scale weight type WPT 8.300BC (Radwag, Radom, Poland). Participants were weighed in normal track clothing while sitting in a wheelchair, and the wheelchair mass was subtracted from the total recorded mass. Aerobic Performance. Each participant performed a maximal exercise test on a motorized driven treadmill (MDT; Saturn R, H-P-Cosmos, Nussdorf-Traunstein, Germany) originally adapted for wheelchairs. The treadmill was connected online to a personal computer. ParaGraphics Software (H-P-Cosmos, Nussdorf-Traunstein, Germany) was used to monitor and collect treadmill data speed and exercise time. VO 2 peak was assessed using the maximal exercise test based on a continuous incremental test protocol to voluntary fatigue. Ventilation (V E ) and VO 2 peak were measured via open circuit spirometry (Vmax metabolic system, SensorMedics, Yorba Linda, USA). Peak oxygen consumption was defined as the highest a participant achieved during the maximal exercise test and was expressed as an absolute value in liters per minute. The relative peak oxygen consumption (rvo 2 peak) with respect to body mass was expressed as milliliters per minute per kilogram. Ventilation and gas exchange were measured breath-by-breath, and data were averaged over 10 s. Anaerobic Performance. To determine anaerobic power and capacity, the Wingate Anaerobic Test (WAnT) was used with an arm crank ergometer (ACE; Angio; Lode BV, Groningen, The Netherlands). The reliability and validity of arm cranking for measuring anaerobic performance in persons with SCI was established by Jacobs, Mahoney, and Johnson (2003). The ergometer was connected inline to a personal computer. The WAnT Software Package and interface RS232 (Lode BV, Groningen, The Netherlands) were used to collect and calculate data. Four indexes were measured during the WAnT: peak power output (PP), defined as the highest 5-s power output; mean power output (MP), the average power sustained throughout the 30-s period; the lowest power output (LP); the lowest 5-s power output; and time (tpp) to achieve PP. The WAnT Software Package also calculated: fatigue index (FI) as the percentage of decline in power output (FI = PP - LP/PP x 100), relative peak power output (rpp), and relative mean power output (rmp) with respect to body mass. Skill Performance. To assess sport-specific skill performance, we used the Beck Battery of Quad Rugby Skill Tests. Yilla and Sherill (1998) established reliability and validity of the Beck Battery of Quad Rugby Skill Tests, and the battery was administered according to the test manual (Yilla, 1993). All tests were performed on a hardwood surface in the same sport hall. Each participant used his own rugby competition chair. The battery included five tests: (a) maneuverability with the ball (Test 1), which measured maneuvering skill through the course of gates while bouncing a ball at least once every 10 s; the score was the total number of gates completed in 30 s; (b) pass for accuracy (Test 2), which measured passing skill for accuracy; the score was the total point value for three at- Table 1. Demographic information about wheelchair rugby players Group n Age Height Body mass Time since Wheelchair rugby (years) (m) (kg) injury (years) experience (years) M SD M SD M SD M SD M SD I II III IV Note. M = mean; SD = standard deviation. RQES: March

5 tempts; (c) picking (Test 3), which measured the skill of setting double picks on each chair in the course; the score was the time taken to complete the 18-m course with six chairs; (d) sprinting (Test 4), which measured sprinting, with the score being the time taken to complete the 20-m sprint; and (e) pass for distance (Test 5), which measured passing skill for distance, with the score being the total point value for three attempts (Yilla & Sherrill, 1998). Testing Procedure Testing took place between 8:00 a.m. and 4:00 p.m. The participants were asked to refrain from taking caffeine, nicotine, and alcohol for at least 5 hr prior to testing and from taking meals for at least 1.5 hr prior to testing. A general practitioner examined participants, which is a standard procedure in Poland prior to beginning laboratory performance tests. Participants completed a personal questionnaire to provide data on age, height, date of disability, wheelchair rugby classification, and experience. Subsequent to that, data on body mass were collected as described eralier. Participants then performed the test on a motorized driven treadmill with their own daily use wheelchairs. The test protocol consisted of a 5-min warm-up at 2 km h - ¹. Immediately following the warm-up, athletes started the continuous incremental test at a set speed of 4 km h - ¹. After 3 min and every 3 min thereafter, the speed increased by 2 km h - ¹ until voluntary fatigue. Participants were verbally encouraged to give maximal effort. After a 2-hr rest, participants performed the WAnT with the ACE (Inbar, Bar-Or, & Skinner, 1996). The athletes sat in their own braked wheelchairs held by two research team assistants. The ACE axis height was at participant s shoulder level. The horizontal distance from the ACE was chosen to allow for a slight elbow flexion at the furthest point of the cranking movement. For participants with severe hand function impairment, an elastic bandage was used to fix their hands to the handlebars. The test protocol consisted of a 2-min warm-up cranking at 60 rpm without resistance. The Wingate test resistance equated to 1 3.5% of body mass. Braking force optimization was based on the Jacobs, Johnson, Mahony, Carter, and Somarriba (2004) recommendations of resistance loading during arm WAnT in individuals with quadriplegia. Each participant cranked as fast as possible, and measuring began as soon as the system registered 25 rpm. The counting of revolutions lasted exactly 30 s (Lode BV, 1998). Participants received verbal encouragement throughout the test. After 2 hr of rest, the athletes took part in the wheelchair rugby skill performance assessment. Before commencing the Beck Battery of Quad Rugby Skill Tests, participants had a 10-min structured group warm-up. Then each athlete completed two trials of all tests, with a minimum 2-min rest between trials. The total score for each test was the average from two trials. Data Analysis Data were analyzed using the STATISTICA 7.1 package (StatSoft, Cracow, Poland). A one-way analysis of variance (ANOVA) was used to compare the four groups on the three performance parameters. A Tukey s post hoc analysis for unequal sample sizes was used to determine group differences. An alpha level of p.05 was used as the criterion for statistically significant differences among groups. The effect size was determined by calculating the omega squared (ω 2 ) for all statistically significant results. The values of ω 2 >.15, >.06, and >.01 were typically considered to represent large, medium, and small meaningfulness of results, respectively (Keppel, 1991). Results Participants demographic data are presented in Table 1. A one-way ANOVA indicated no significant differences among the four groups in age, F(3, 26) = 0.12, p =.95; height, F(3, 26) = 0.52, p =.67; body mass, F(3, 26) = 1.7, p =.19; time since injury, F(3, 26) = 1.07, p =.38; and wheelchair rugby experience, F(3, 26) = 0.4, p =.75. The groups were similar across all demographic variables, although Group IV athletes weighed somewhat more than those in the other groups. Aerobic Performance An ANOVA indicated significant differences among the four groups in minute ventilation, F(3, 26) = 4.60, p =.01, ω 2 =.265; peak oxygen consumption, F(3, 26) = 4.41, p =.012, ω 2 =.254; and exercise time F(3, 26) = 5.37, p =.005, ω 2 =.305. However, there was no significant difference among the four groups for relative peak oxygen consumption (rvo 2 peak), expressed in milliliters, with respect to body mass, F(3, 26) = 2.54, p =.078 (see Table 2). The results of Tukey s post hoc analyses (see Table 2) revealed significant differences between Groups I and IV for minute V E, VO 2 peak, and exercise time. There were also significant differences between Groups I and III for exercise time. The effect size (ω 2 ) showed a large meaningfulness (ω 2 >.15) of results for V E, VO 2 peak, and exercise time. Anaerobic Performance An ANOVA revealed significant differences among the four groups (see Table 3) in peak power, F(3, 26) = 22.14, p <.001, ω 2 =.679; relative peak power, F(3, 26) = 17.66, p <.001, ω 2 =.622; mean power, F(3, 26) = 20.79, p <.001, ω 2 =.664; relative mean power, F(3, 26) = 16.55, p <.001, ω 2 =.609; the lowest power, F(3, 26) = 17.20, p <.001, ω 2 =.618; and time to achieve peak power, F(3, 26) = 14.74, p <.001, ω 2 =.579. There was no significant differ- 64 RQES: March 2011

6 ence among the groups for the fatigue index, F(3, 26) = 2.28, p =.102 (see Table 3). Tukey s post hoc tests showed that Group I was significantly different from Group II (except PP and LP) and Groups III and IV in all anaerobic parameters. There were also differences between Groups II and IV for PP, rpp, MP, rmp, and LP. However, Group II was not significantly different from Group III (except PP), nor was Group III significantly different from Group IV. The meaningfulness of results (effect size) was large (ω 2 >.15) for PP, rpp, MP, rmp, LP, and tpp. Skill Performance The ANOVAs identified significant differences among the four groups for the five sport-specific tests (see Table 4): Test 1, F(3, 26) = 7.36, p =.001, ω 2 =.390; Test 2, F(3, 26) = 4.72, p =.009, ω 2 =.271; Test 3, F(3, 26) = 7.20, p =.001, ω 2 =.383; Test 4, F(3, 26) = 16.36, p <.001, ω 2 =.606; and Test 5, F(3, 26) = 5.05, p =.006, ω 2 =.288. Post hoc analysis revealed that Group I significantly differed in all tests from Group III (except Test 2) and Group IV (except Test 5). There were also differences between Groups I and II for Tests 3 and 4. There were no significant differences in all performance tests between Groups II and III, Groups II and IV, and Groups III and IV. There was a large effect size (ω 2 >.15) for all tests. Discussion The major finding of this study was that most differences were between Group I (0.5) players and all others. Another important finding was that for all other groups, adjacent groups did not differ, except for one measure (peak power). That is, Group II players (1.0 and 1.5 points) were not significantly different from Group III players (2.0 and 2.5 points), nor were Group III players (2.0 and 2.5) significantly different from Group IV players (3.0 and 3.5) in anaerobic, aerobic, and sport-specific skill. Aerobic Performance Aerobic performance identified the fewest differences between groups, all of which were between Group I and other groups. This would indicate it is the least sensitive measure for identifying differences between classes. Table 2. Differences between players classification groups in aerobic performance parameters (Tukey s post hoc analysis) I II III IV I vs. I vs. I vs. II vs. II vs. III vs. M SD M SD M SD M SD II III IV III IV IV V E (l min - ¹) * VO 2 peak (l min - ¹) * rvo 2 peak (ml min- ¹ kg - ¹) Exercise time (min) * * Note. M = mean; SD = standard deviation; V E = minute ventilation; VO 2 peak = peak oxygen consumption; rvo 2 peak = relative peak oxygen consumption. *p <.05. Table 3. Differences between players classification groups in anaerobic performance parameters (Tukey s post hoc analysis) I II III IV I vs. I vs. I vs. II vs. II vs. III vs. M SD M SD M SD M SD II III IV III IV IV PP (W) *** *** * *** rpp (W kg - ¹) ** *** *** *** MP (W) * *** *** *** rmp (W kg - ¹) ** *** *** * LP (W) ** *** ** tpp (s) *** *** *** FI (%) Note. M = mean; SD = standard deviation; PP = peak power; rpp = relative peak power; MP = mean power; rmp = relative mean power; LP = the lowest power; tpp = time to achieve PP; FI = fatigue index. *p <.05. **p <.01. ***p <.001. RQES: March

7 Bearing in mind the study by Hopman et al. (1996), which identified aerobic performance as the one least likely to be directly changed by wheelchair rugby training, the findings of the present study were expected. The results of peak oxygen consumption, which ranged from 1.6 to 2.4 l min - ¹ in this study, are surprisingly higher than the VO 2 peak values reported for active men with quadriplegia in a review study by Haisma et al. (2006), which ranged from 0.76 to 1.03 l min - ¹. The differences in experimental protocols for VO 2 peak examinations between the current study and those reviewed by Haisma et al. (2006) may explain this. Recently, Janssen et al. (2002) attempted to prepare normative values of physical capacity in persons with SCI. The VO 2 peak values in the current study represented excellent physical capacity according to Janssen et al. In the present study, rvo 2 peak with respect to body mass was not significantly different among the four groups. Interestingly, Group II players achieved higher rvo 2 peak values than Group III (26.4 ml min - ¹ kg - ¹, 25.6 ml min - ¹ kg - ¹, respectively). Although several studies (Coutts et al., 1983; Eriksson et al., 1988; Janssen et al., 1993; Janssen et al., 2002) indicated the relationship between lesion level and aerobic capacity in individuals with SCI, it should be noted that sample sizes usually combined persons with quadriplegia and paraplegia, resulting in conclusions limited to differences between individuals with high and low spinal cord lesions. We have not yet found published evidence identifying aerobic capacity separately in active individuals with quadriplegia with regard to their spinal cord lesion or sport classification. Bernard, Mercier, Varray, and Prefaut (2000) reported that in well trained wheelchair athletes with paraplegia the peak cardiorespiratory responses during incremental wheelchair ergometry may not be related to the lesion level. Also, specific cardiorespiratory adaptations that occur during maximal exercise testing in athletes with paraplegia may be different from athletes with quadriplegia because of disrupted sympathetic stimulation to the myocardium. Further research is needed to determine the influence of neurological level on VO 2 peak in elite athletes with quadriplegia. In addition, only minute ventilation and VO 2 peak, expressed as an absolute value in liters per minute, were significantly different between Groups I and IV. These results are in accordance with Vanlandewijck, Spaepen, and Lysens (1995) study of aerobic capacity in wheelchair basketball players, in which they observed no differences in rvo 2 peak among Classes II, III, and IV (in a four-class wheelchair basketball functional system). They questioned whether aerobic capacity is a determining factor in wheelchair basketball performance. Grimby, Broberg, Krotkiewska, and Krotkiewski (1976) documented that a preponderance of Type IIb (fast glycolytic) motor units with a concomitant reduction in Type I (slow oxidative) motor units in the lower extremity muscles (vastus lateralis) and the upper extremities (deltoid) occurs in individuals with quadriplegia. This tendency may explain the limited aerobic capabilities in individuals with quadriplegia. The lack of significant differences in VO 2 peak among the four groups of wheelchair rugby players in our study may also be explained by specificity in wheelchair rugby, which is dominated by intense exercise sessions that improve anaerobic, rather than aerobic, capabilities. Because wheelchair rugby includes elements of wheelchair basketball and the assumptions of wheelchair rugby classification are similar to wheelchair basketball classification, it may be important for future studies to compare classification systems in both sports. Anaerobic Performance Anaerobic performance was the most sensitive in detecting differences between the groups, with a number of comparisons revealing significant differences below the.001 level. A study by Morgulec et al. (2005) concerning the anaerobic power of individuals with quadriplegia revealed a significant relationshp between lesion level and relative mean power. However, it should be noted that Table 4. Differences between players classification groups in the Beck battery of skill tests (Tukey s post hoc analysis) I II III IV I vs. I vs. I vs. II vs. II vs. III vs. M SD M SD M SD M SD II III IV III IV IV Test 1 (pt) ** ** Test 2 (pt) * Test 3 (s) * ** ** Test 4 (s) ** *** *** Test 5 (pt) ** Note. M = mean; SD = standard deviation; Test 1 = maneuverability with the ball; Test 2 = pass for accuracy, Test 3 = picking, Test 4 = sprinting; Test 5 = pass for distance. *p <.05. **p <.01. ***p < RQES: March 2011

8 Morgulec et al. computed correlation coefficients for both sedentary and active men with quadriplegia together. In the present study, the anaerobic performance (rpp, MP, rmp, tpp) of Group I (0.5 point players) differed from the other three groups of wheelchair rugby players. There were also differences between Groups II and IV; however, Group II was not significantly different from Group III, nor was Group III significantly different from Group IV. These results are in agreement with the Hutzler et al. (1998) study of wheelchair basketball players anaerobic capacity, in which the authors demonstrated significant differences in peak power only between wheelchair basketball players from Classes 1 and 4.5 and from Classes 2 and 4.5. This suggests that the anaerobic performance of both wheelchair rugby and basketball players does not reflect the differences between athletes from border classes (i.e., Classes 0.5 and 1 1.5, and 2 2.5, and and in wheelchair rugby or Classes and 2 2.5, and 3 3.5, and and in wheelchair basketball). Interestingly, in this study wheelchair rugby players aerobic and anaerobic performance did not depend on the athletes classification points. Thus, future research should be designed to examine the dynamics of wheelchair rugby to determine whether aerobic or anaerobic capacity is more specific to wheelchair rugby. The indications from this study were that anaerobic performance was more specific to wheelchair rugby. Skill Performance The analysis of sport-specific skills in wheelchair rugby athletes revealed no significant differences between Groups II to IV (Class 1 1.5, 2 2.5, and points) in all tests. Although there are other differences between players according to the IWRF functional classification system, there seemed to be none among Groups II, III, and IV in executing maneuverability with the ball (Test 1), pass for accuracy (Test 2), picking (Test 3), sprinting (Test 4), and pass for distance (Test 5). Overall, Group I athletes (Class 0.5) differed from the other three. Findings of previous studies investigating the classification system in wheelchair basketball also identified differences between lower and higher functioning athletes but not between all the classes (Hedrick & Brasile, 1996; Molik & Kosmol, 2001; Vanlandewijck et al., 1995). The results of the present study do not support those of Malone et al. (2006) that the classification system adequately divides wheelchair rugby players based on skill. The authors indicated significant correlations among players classification and skill test results. In this context, it is important to question whether that correlation is an adequate methodology for examining classification systems in wheelchair rugby. Moreover, in the present study, there was a tendency in all skill tests, with the exception of Test 2, for Group III players to perform slightly better than Group IV players. In this study, performance was, environmentally, the closest indicator of in-game performance. Although, the IWRF classification system is based on medical, functional, and observational criteria, it is important to review whether on-court performance should receive greater emphasis in the classification procedure. Currently, the athlete is observed on the court, only if the results of manual muscle tests, functional movement tests, and trunk tests are inconclusive. Thus, a sport-specific part of wheelchair rugby classification (court observation) seems to be applied only exceptionally. We hope a new project using international wheelchair rugby classification databases (Altman et al., 2006) will also include detailed information about the players on-court performance. In summary, the results of this study show that anaerobic, aerobic, and sport-specific skill performance of wheelchair rugby players is not dependent on a player s classification. It is evident that 0.5 players present lower performance in comparison with all other players. Generally, there is a tendency for athletes with higher classification points to perform better. However, lack of significant differences in aerobic, anaerobic and sport-specific skill performance between Groups II IV (Class 1 1.5, and 3 3.5) underlines the need for continued examination of the IWRF classification system with an emphasis on on-court performance. We have little doubt that the tools used in the current study were insufficient to comprehensively measure the complex factors underlying the classification differences in wheelchair rugby; however, this study lays the foundation for further examinations of wheelchair rugby classification using alternate measures. Other limitations of this study are that we did not examine all seven IWRF classification levels and that our sampling methodology did not reveal interclass differences. It is critical that the academic community continues to develop and refine measurement tools and procedures to help develop equitable classification systems, not only in wheelchair rugby but in all disability sports. References Altman, V. C., Hart, A., & Parkinson, A. (2006). Wheelchair rugby classification datebase: Aid to the improvement of classification. Paper presented at the Vista 2006 Conference on Classification: Solution for the Future, Bonn, Germany. Bernard, P. 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