### Abstract
Wheelchair basketball met a rapid growth in recent decades and became one of the most popular and spectacular sports for people with disabilities. Researchers’ efforts to perform tests evaluating the physiological and technical characteristics of the disable athletes have been based on the adoption of tests, used for healthy athletes (7, 15). In addition, different types of disabilities obligated the International Wheelchair Basketball Federation to establish classification degree for the athletes, ranging from 1 to 4.5, according to their disability. The purpose of this study was to evaluate the Greek elite basketball players’ technical skills and to compare their performance, (a) with their classification degree and (b) with recent literature. Fourteen (N=14) Greek wheelchair basketball players, all members of the national team, volunteered to perform six skill tests: (a) 20m sprint, (b) free throws, (c) lay-ups, (d) obstacle dribble, (e) pass for accuracy, and (f) pass for distance. The high classification degree athletes, demonstrated significantly higher performance than those with low classification, only in obstacle dribble test (p <.01), but the trend indicated that athletes with high classification degree demonstrated better performance on tests requiring physical abilities (sprint, lay-ups, obstacle dribble, pass for distance), while those with low classification degree performed better on tests requiring skills and concentration (free throws, pass for accuracy). These results are in accordance with recent literature, although Greek basketball players, demonstrated lower performance compared with those of other countries, where wheelchair basketball is widespread (13). The difference between high and low classification players in obstacle dribble test, caused to the lack of abdominal muscles, while overall performance is affected by the frequency of training and years of involvement with the sport, before the time point of injury (9).
**Key words:** wheelchair, basketball, technical skills
### Introduction
Sporting activities for people with physical disabilities became widespread in recent years. Wheelchair basketball, which is regarded as one of the most popular and spectacular sports for people with disabilities, devised at the end of the Second World War. Specifically, in 1944 the British government commissioned Dr. Guttmann to establish a foundation for care and hospitalization of world-war II spinal cord injured soldiers, in the area of Stoke Mandeville Hospital. Specifically, the team called “The Flying Wheels of Birmingham” is the one that has the legal right to invoke that have devised the wheelchair basketball (1946). The evaluation of the wheelchair basketball players’ technical skills has interested researchers and trainers in the past (4, 14-15). The evaluation methods for the technical characteristics of wheelchair basketball players, mainly based on similar tests used for healthy players (1-2, 11).
The ability to perform the technical skills required for the sport, characterized by the different type and degree, of the players’ disabilities. Each athlete is classified according to degree of disability, and the ability to perform certain tests such as wheelchair sprint, stopping, obstacle dribbling, holding the ball, etc. The classification system for wheelchair basketball, which has been established by the International Wheelchair Basketball Federation (IWBF), with five classification points (1-4.5), differs than U.S.A. applied system, which classifies the players in a three points scale (1-3). The main purpose of the studies so far, is to evaluate the athletes with different classification, and to investigate methods to improve their technical skills.
Brasile (4) demonstrated the performance of wheelchair basketball players which were classified according to the U.S.A. applied system (Classification I, II and III). Participants were evaluated in the following skill tests: (a) obstacle dribble, (b) free-throws, (c) dribbling and shooting the ball, and (d) pass for accuracy. The results showed that: (a) the classification II and III athletes demonstrated higher performance than the others, and (b) classification II athletes demonstrated highest performance.
Moreover, Vanlerberghe and Slock (14) evaluated 30 wheelchair athletes which were classified in the 3 points scale (I, II, III) and they applied: (a) two tests for shooting accuracy (shot under the basket and rebound; obstacle dribble, shot and rebound), (b) two tests for ball-handling (obstacle dribble and dribble around wheelchairs), and (c) two tests for passing ability (speed pass and long pass).
Results revealed significant differences between athletes with different physical disabilities. Athletes of III classification revealed the highest performance, while athletes of I classification revealed the lowest. However, researchers have argued that these specific skill tests can hardly be a reliable method for the evaluation of the wheelchair basketball players.
Also, Brasile (5) divided a sample of 79 wheelchair basketball athletes into three groups, according to their classification in order to evaluated their technical ability in six skill tests: (a) obstacle dribble, (b) 1 minute free throws using the strong hand, (c) 1 minute free throws using the weak hand, (d) pass for accuracy using the strong hand, (e) pass for accuracy using the weak hand and (f) 20m speed run. The skill tests’ results revealed that, athletes of II and III classification referred similar performance between them, but both of them higher than the athletes of I classification. These findings led the researcher to the conclusion that skill tests’ results are influenced by both of the training time and the previous experience in basketball.
Similar results were referred in a recent study by Ergun, Duzgun and Aslan (9), which evaluated 32 wheelchair basketball players. Subjects with low disability lagged behind in lay ups test, in 20m speed run, in shooting around the basket, as well as in obstacle dribble. Additionally, there were detected significant differences between athletes of different coaching experience to the tests of 20m speed run, obstacle dribble and passing for accuracy. Moreover, “age” may be an important factor that affects the performance of the athletes in wheelchair basketball.
Brasile (6) applied six field tests to evaluate twelve male and twelve female wheelchair basketball athletes in the following tests: (a) obstacle dribble, (b) free throws, (c) rebound and shot with the strong hand, (d) rebound and shot with the weak hand, (e) pass for accuracy with the strong hand and (f) pass for accuracy with the weak hand. Within the female group were revealed significant differences in tests requiring capability and discipline (rebounding and shooting the ball, obstacle dribble). In contrast, male athletes revealed improved performance in tests requiring higher power level and especially to those that were related with distance (passing for accuracy and free throws).
Finally, Molik et al. (13) evaluated 109 Poles and Lithuanian wheelchair basketball players in six skill tests. The results of the study revealed that athletes with low classification demonstrated lower performance, compared to athletes with a high classification degree. Particularly, no significant differences were detected between athletes of 1 and 2 classification degree. Reversely there were detected significant differences between athletes of 3 and 4.5 classification degree.
As is evident from reviewing the literature, the topic of wheelchair athletes’ skills is incomplete, and more incomplete regarding the high level athletes. The purpose of the present study is (a) to document the performance of elite basketball players’ in the technical skills, (b) to compare their performance in relation to their classification degree, and (c) to compared and discuss their performance with previous studies.
### Methods
#### Participants
Fourteen (N=14) wheelchair basketball athletes aged 30.1±6.6, all of them members of the national team, volunteered to participate in the present study (See Table 1). The types of their disability were the following: (a) one athlete with incomplete quadriplegia (injury on 6th and 7th cervical), (b) seven athletes with paraplegia (injury on 7th cervical to 12th thoracic), (c) one athlete with poliomyelitis and (d) six amputated athletes. They were divided in two groups of 7 athletes, according to their classification. The first group (n1=7) consisted from athletes of 1-2.5 and the second (n2=7) of 3-4.5 classification degree.
#### Skill tests
The six skill tests which assign the technical characteristics of the wheelchair basketball players and were applied in the present study are the following:
*20m speed run:* Subject takes a position behind the baseline and on the signal starts covering a 20m distance as fast as possible. In a two-minute period the subject had two attempts and the best is recorded (See Figure 1).
*Free throws:* Subject shoots 40 free throws in a series of 20 at a time. A 2-minutes rest inserted between the trials. One point was given for each basket made (See Figure 2).
*Obstacle dribble:* Subject starts on the signal at the tight side of the first obstacle and maneuvers through the course as fast as possible, pushing the wheelchair and dribbling the ball, accordingly the U.S.A. NWBA rules. The test is repeated without rest for one more time. Each dribbling violation adds 5 seconds to the trial time and each time the subject, ball, or wheelchair touch an obstacle, one second added to the trial time. One test trial was given to the subjects, for the familiarization with the test (See Figure 3).
*Lay-up:* Two cones are positioned on the 3-point line, perpendicular to the intersection, of the side lines of the free throw lane and the baseline. The subject takes position out of the 3-point line and starts with the signal to make as many lay-ups as possible within two minutes. After each attempt, he takes his own rebound, dribbles the ball around the opposite cone, preparing for the next lay up. The score was the total amount of the attempts, plus the total number of the successful lay ups (See Figure 4).
*Pass for distance:* The subject places the wheelchair so that the front wheels are behind the base line. Using the chest pass, he tries to pass the ball as far as possible. Subject was performed six attempts and the total of the measured distance was recorded (See Figure 5).
*Pass for accuracy:* The target in the specific test are three concentric rectangles of different sizes (50.8cm X 25.4cm, 101.6cm X 63.5cm and 152.4cm X 101.6cm), drown to smooth wall. The base of the larger rectangle is 60.96cm from the ground and the passing line is 10m (for 2-4.5 classification) or 7.5m (for 1 and 1.5 classification) from the wall. Subjects at the signal take position behind the line and perform 10 passes towards the wall any way the wish (i.e., chest pass, overhead, baseball), but discount any passes where the ball bounces first. If the ball hits the line or inside the smallest rectangle, subjects received 3 points which was the highest score. Two points received for the middle and one for the outer rectangle. Subjects should receive three warm up tosses from their distance and finally, only one trial of ten passes was allowed (See Figure 6).
#### Statistical analysis
Six separate (one for each skill test) independent samples t-tests were conducted to detect possible differences between the groups, and for all the carried skill tests. Significance level was set at p<0.05.
#### Classification
It is very possible, wheelchair basketball athletes because of their differences in disability degree, mobility, physical condition and training experience, to perform the technical skills by a completely different way. The skill’s performance was evaluated during games, from specialized observers called “classificators.” A basketball team comprehends athletes with high disability degree such as spinal cord injuries (e.g., quadriplegia), as well as athletes with low disability degree (e.g., amputation, other disabilities). The athletes are classified from 1 to 4.5, accordingly their basketball skills performance. The high classification degree corresponds to athletes with high functional capacity (therefore lower level of disability). The aim of this classification method is the compulsory participation of all the disable athletes in the games. These regulations have been applied since the early 1940’s, years of the game’s establishment. The first classification methods were based on the athletes’ anatomical characteristics, rather than their functional, so the athletes were classified with base their disability and not on their performance in games. Since 1984 a new classification system is in operation which primarily classified the athletes in four degrees (1, 2, 3, 4). Later, some changes were demonstrated, but the most important was the addition of the half degrees (1.5 – 2.5 – 3.5 – 4.5). The U.S.A National Wheelchair Basketball Association (N.W.B.A.) has established a different classification system, which is consistent by three degrees (1 – 2 – 3). So, the athletes are classified and the total of the in-bounce players’ degree must not exceed a specific number. The International Wheelchair Basketball Federation decided for the international games and tournaments, the limit total degree for the in-bounce players to be the 14. For the national and local championships, the Federations allow the participant teams to come in the games with more limit degrees (e.g., 14.5 or 15).
### Results
Table 2 presents the athletes’ classification and their performance in all the technical skills.
The results of the t-test process are presented in table 3. Significant differences detected only for the obstacle dribble test.
### Discussion
This study examined the performance of a sample of high level wheelchair athletes in basketball skills. It was well-documented that athletes with low classification degree, demonstrated lower performance than those with high classification, but not statistically significant. However, significant differences were presented only to the obstacle dribble test. These results are in accordance with previous studies of considerable researchers (7-8, 14). It is discussed below the results regarding the skill tests separately.
#### 20m speed run
For wheelchair basketball the speed ability holds an important role. Specifically, after adjusting the 24¨ regulation, the individual and team speed, became imperative. Brasile (4-5) referred differences in speed run, between the athletes of 2-3 and 1 classification degree, while Ergun et al (9) referred that training experience affects the speed run ability. Contrary to these researches, no significant differences were detected between the two groups in the present study but, on the one hand Brasile (3-8) used different classification method and on the other hand Ergun (9) detected differences only between the athletes of various experience.
Free throws
Although significant differences were not detected between the groups in this test, it is obvious that small differences, appears to be between the groups (20.7 vs 18.4). The results are in accordance with resent literature however, a point of attention regarding free throw shooting performance is the different technique between the players (10, 12), the different type of the wheelchair, their age and the training level before the injury (5), as well as after it (9).
#### Obstacle dribble
Regarding the obstacle dribble, significant differences were observed between the groups in the present study (55.5sec vs 47.1sec, p<0.001). These results are in accordance with literature, while in both of the studies (8-9, 14) which investigated obstacle dribble, were detected significant differences between the athletes with different classification level. Obviously, in this test, many repeated changes of direction in conjunction with controlling the ball, requiring full activation of the abdominal muscles. In these muscle groups, the difference between athletes of varying classification level, is obvious and has an important role in performance, especially in tests involving abrupt changes of direction. An important finding regarding the obstacle dribble test is the difference between Greek and U.S.A. wheelchair athletes. Vanlerberghe and Slock (14), referred values of 47.1 and 43 sec accordingly for low and high classification athletes.
These differences in performance among the Greek and U.S.A. wheelchair athletes, can be justified by the low level of Greek wheelchair basketball and the fact that their involvement in the sport is more leisure, as well as they do not train more than three times a week during the season. On the other hand, basketball in the U.S.A. is highly developed and the national team is among the top teams in the world while the Greek wheelchair basketball national team, is classified in division III of Europe.
#### Lay ups
Contrary to Ergun et al. (9) results, in this study were not detected significant differences between the groups. Specifically, the low classification athletes referred 9.1±2.3 purposeful efforts, while the high classification athletes 11.1±2.2. Although there is a lack of significance, the difference between the groups (9.1 vs 11.1) highlights a strong trend of the high classification athletes, to perform better scores in the specific test.
#### Pass for accuracy
Significant differences between these groups were not observed. However, it has to be noticed that in this test, the low classification athletes were performed their efforts closer to the target, compared to their co-participants with high classification level, which may have influenced the results. It seems that there is need for further investigation, to explore a better method, for assessing the passing test for accuracy.
#### Pass for distance
No significant differences were detected between the groups (12.1 vs 10.5). These results are in accordance with Vanlerberghe and Slock (14), they are reasonable and explained by the fact that the upper body of the athletes is not damaged, so they don’t lack of power and they can throw the basketball away.
### Conclusions
This study investigated the technical characteristics of elite basketball players with disabilities. Overall, although significant differences were not revealed between high and low classification athletes, the trend indicates that athletes with high classification degree are better on tests requiring physical abilities, while those with low classification degree performed better on tests requiring skills and concentration. It is also important to take into consideration the fact that the Greek athletes with disabilities do not train regularly and intensively and had no training experience before the injury. Future research should focus on planning and application of training programs, in order to ascertain the influence of organized and intensive training to the improvement of their physical and technical skills.
### Application In Sports
The organized and intensive training in athletes with disabilities is efficient and it is very important for their performance, from time to time to be evaluated through valid and reliable tests. The frequent applications of test functions as motive for the athletes, so they are more concentrated, energetic, and effective during practice.
### Acknowledgments
The authors thank all the wheelchair basketball players, participating in this study, for their maximum efforts to achieve the best performance. Their contribution made this research possible.
### Tables
#### Table 1
Anthropometric characteristics of Greek elite wheelchair basketball players
| N | Disability | Class | Age | Weight (kg) | High (cm) |
|---|---|---|---|---|---|
| 1 | PARA | 1.0 | 29 | 65 | 180 |
| 2 | TETRA | 1.0 | 25 | 74 | 177 |
| 3 | PARA | 1.0 | 30 | 75.5 | 180 |
| 4 | PARA | 1.5 | 23 | 120 | 188 |
| 5 | PARA | 1.5 | 29 | 67.5 | 189 |
| 6 | PARA | 2.0 | 39 | 85 | 180 |
| 7 | PARA | 2.0 | 22 | 62.8 | 170 |
| 8 | PARA | 3.0 | 30 | 64 | 178 |
| 9 | POLIO | 3.0 | 40 | 74.4 | 170 |
| 10 | AMP | 4.0 | 43 | 96.6 | 180 |
| 11 | AMP | 4.5 | 31 | 78 | 180 |
| 12 | AMP | 4.5 | 28 | 61 | 180 |
| 13 | AMP | 4.5 | 22 | 87.4 | 188 |
| 14 | AMP | 4.5 | 31 | 113.2 | 200 |
| M | 30.1 | 80 | 181.4 | ||
| SD | 6.6 | 18.5 | 7.8 |
#### Table 2
Technical characteristics of Greek elite wheelchair basketball players
| N | Classification | Lay up | Free throws | Long pass | Pass for accuracy | 20m sprint | Obstacle dribble |
|---|---|---|---|---|---|---|---|
| 1 | 1 | 11 | 19 | 25 | 10.5 | 5.8 | 55.4 |
| 2 | 1 | 9 | 18 | 19 | 10.4 | 5.7 | 57.4 |
| 3 | 1 | 6 | 23 | 15 | 10.4 | 6.1 | 55.3 |
| 4 | 1 | 6 | 13 | 20 | 9 | 6.3 | 58.9 |
| 5 | 1.5 | 10 | 26 | 21 | 8.7 | 7.0 | 56 |
| 6 | 2 | 12 | 27 | 11 | 13.6 | 5.7 | 56.8 |
| 7 | 2 | 10 | 19 | 17 | 12 | 5.1 | 49 |
| M | 9.14 | 20.71 | 18.28 | 10.66 | 5.96 | 55.54 | |
| SD | 2.34 | 4.92 | 4.50 | 1.69 | 0.59 | 3.15 | |
| 8 | 3 | 8 | 15 | 13 | 12.4 | 5.2 | 47.1 |
| 9 | 3 | 14 | 22 | 17 | 9.3 | 5.7 | 48.9 |
| 10 | 4 | 13 | 19 | 17 | 8.9 | 6.0 | 50.7 |
| 11 | 4.5 | 12 | 24 | 12 | 13.8 | 5.2 | 44.4 |
| 12 | 4.5 | 10 | 19 | 19 | 12.9 | 5.2 | 43.1 |
| 13 | 4.5 | 12 | 20 | 16 | 15.2 | 6.0 | 51 |
| 14 | 4.5 | 9 | 10 | 11 | 12.1 | 5.7 | 44.8 |
| M | 11.14 | 18.43 | 15 | 12.09 | 5.57 | 47.14 | |
| SD | 2.19 | 4.65 | 3 | 2.28 | 0.37 | 3.16 | |
#### Table 3
t-test results for the six skill tests within the group
| test | t | p |
|---|---|---|
| Lay up | -1.65 | 0.12 |
| Free throws | 0.89 | 0.39 |
| Long pass | 1.61 | 0.13 |
| Pass for accuracy | -1.32 | 0.21 |
| Sprint | 1.46 | 0.17 |
| Obstacle dribble | 4.98 | 0.0003 |
### Figures
#### Figure 1
20m speed run
#### Figure 2
Free throws. 2 series of 20 shot
#### Figure 3
Obstacle dribble
#### Figure 4
Lay-ups (2 min)
”)
#### Figure 5
Long pass (6 trials)
”)
#### Figure 6
Pass for accuracy (10 trials)
”)
### References
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### Corresponding Author
N. Apostolidis, Phd
National & Kapodistrian University of Athens, Faculty of Physical Education & Sport Science
Daphne – Athens, 17237 Greece
<napost@phed.uoa.gr>
+302107276085
Dr. E. Zacharakis is Lecturer to the Faculty of Physical Education and Sport Science of the Athens University. He is teaching Basketball techniques and tactics (Undergraduate). He was head coach of the Greek wheelchair basketball team, participated to the Olympic Games in Athens 2004. His research interest is focused on wheelchair basketball, concerning the technical and physiological characteristics.
