時間切迫が運動スキルの遂行に及ぼす影響

The purpose of this study was to examine the influence of time pressure on the psychological, physiological, and behavioral aspects of a dart-throwing task. Participants (N=25) performed 140 acquisition trials (10 trials×14 blocks) followed by 10 test trials under time pressure. Time pressure was induced by instructing the participants to complete 10 test trials within the duration of the longest acquisition block. Dart-throwing movements were videotaped for 2-dimensional kinematic analysis. The results showed that the dart scores decreased from the last acquisition block to the test (p<.01), and that heart rate (p<.01) increased from the acquisition to the test. An analysis of a questionnaire revealed that conscious control of movements (p<.05) and attention to time (p<.01) increased from the acquisition to the test. The inter-trial dart throwing interval (p<.01) decreased from the acquisition to the test. In addition, the minimum angle (p<.01) and mean angular velocity (p<.05) of the elbow joint in the take-back phase increased from the acquisition to the test, indicating that the take-back movement became smaller and faster under time pressure. Although the participants did not have to decrease the inter-trial interval and movement time to complete the test trials within the time limit, it appeared that these behavioral changes were caused by time pressure. In addition, contrary to the inhibition of movement velocity due to performance pressure (Tanaka and Sekiya, 2006), time pressure facilitated movement velocity in the present study, suggesting that different kinds of stressors lead to different movement characteristics.