Control of Accuracy during Movements of High Speed: Implications from Baseball Pitching.

Despite the well-known tradeoff between speed and accuracy, skilled people often demonstrate the ability to maintain high accuracy during fast movements. We focused on two strategies to improve accuracy, thereby increasing the reproducibility of individual parameters (certain parameters are maintained in low variability) and coordinating covariation among parameters (different parameters compensate each other's variability). The objective of this study was to determine whether coordinated covariation among release parameters is used for high accuracy by skilled baseball pitchers. A model was employed to simulate pitch location after eliminating the coordinated covariation by randomly reshuffling the release parameters, and the variability of simulated and measured pitch locations were compared. The results showed that there was no significant coordinated covariation for any of the release parameters for either the vertical or horizontal pitch location supports strategy of increasing the reproducibility of individual parameter. In addition, for the vertical pitch location, because there was coordinated covariation between the release angle and speed in slow pitching, it was suggested that, the higher speed the task requires, the more important the reproducibility of individual parameter becomes.