Upper Extremity Kinematics during Free Throw Shooting of Thai Wheelchair Basketball Players

Wheelchair basketball (WCB) is one of the fastest growing competitive team sports. To score points, free-throw shooting (FTS) is the easiest shot since it is an uncontested shot. Although previous studies have been investigated kinematic of FTS, kinematics of upper extremity has never been reported in Thai WCB players. Understanding upper extremity kinematics is valuable since it can help improve shooting performance. Thus, the purpose of this study was to study upper extremity kinematic during free throws of advanced WCB players. Five male WCB athletes (mean

age

= 27

+

2.9 yrs, mean

weight

61

+

4.2 Kg) volunteered in the study. Participants were divided into two groups: high class (4-4.5 points) and low class (3 – 3.5 points). Seven retroreflective markers were placed on the right side of second metacarpophalangeal joint, the fifth metacarpophalangeal joint, and the radial and ulna styloid processes, the medial and lateral epicondyles and acromion process. Three video cameras were simultaneously recorded FTS motion at the sampling frequency of 30 Hz and synchronized by the light switch. Raw coordinate data were filtered with 4

th

order Butterworth with a cut-off frequency of 4 Hz. Each participant performed FTS for 10 trials which two successful trials of clean shot were averaged and analyzed. Upper extremity angles including shoulder, elbow and wrist were obtained. The Mann-Whitney U test was employed to determine statistical significance between the groups. The results showed that the high class had a greater range of motion of shoulder and elbow than the low class group whereas the low class group used a larger range of motion than the high group. Since the low class group used smaller range of motion at the shoulder and elbow joint, they may compensate at the wrist joint. Nevertheless, no statistical differences of upper extremity angles between the two groups were found (p<0.05). Due to the small sample size, future investigation with larger sample size is warranted.