Abstrakt: |
The choice of attacks by Karate exponents is not well understood but is of importance to coaching practices. This case study explores gaze tracking sequences prior to attacking and seeks possible associative actions performed by the karateka. One Malaysian Karate exponent with over 8 years experience in the National team volunteered to participate in a simulation match of 2 minutes while wearing the Mobile Eye glasses (ASL, USA). Gaze was recorded at 25 Hz and was synchronised with an additional camera (25 Hz) recording the performance from just outside the mat. Gaze fixations were manually coded along 6 different areas (head, above the head, chest, abdominal, arm and leg) of the opponent. Also performance tactics (attack or counter) and actions (lunges, kick, punch and blocks) by the participant were manually notated. Gaze fixation sequences were selected from the start of an action back to when fixation had stabilized after the last action. The sequences were then clustered using the longest common sequence method in the TraMineR package of R-project statistical software. The clusters, similar in fixations sequence and length, were then associated with the tactics and actions performed. In total 23 fixation sequences and a same number of actions were identified. The most frequent and longest fixations were concentrated around the body and head of the opponent. The dendrogram showed three major types of clusters. Type 1 was mostly associated with counter attacks (79%) that included punches (57%). The second and third clusters contained the same number of attacks as counters and were mostly associated with lunges (50%) and kicks (38%). Furthermore looking at the lengths of the sequences within each cluster, type 2 and 3 had longer lengths than type 1. Therefore, these two clusters could essentially be considered as one despite differences in eye fixation sequence. The counter chudan (punch to the body) technique was used the most (7 times) and is associated with cluster type 1. Attacking kicks (5 times) and backward lunges (5 times) on the other hand are associated with the combination of type 2 and 3. However, it is rather the length of the fixation sequence in between the attacks than the area of fixations themselves that was found to be associated with the actions by this karateka. Short fixation sequences evoke a fast punching response. This is likely due to pressured situations where the distance to the opponent was reduced quickly by an attacking opponent. While longer fixation sequences are followed by (evading) lunges and kicks to disrupt the opponent and keep distance from the opponent without a direct attempt to score. [ABSTRACT FROM AUTHOR] |