Evaluation of postural control during quiet standing and aiming tasks in professional and novice archers.

Postural stability is essential for archery performance, as reduced center of pressure (COP) fluctuations enable precise bow alignment and shot accuracy. Although prior studies have shown that professional archers exhibit smaller COP displacements and variability than novices, the structural complexity of postural control in archery has not been examined. In this study, we evaluated COP displacement, variability, and complexity in 8 professional and 8 novice archers during quiet standing and aiming tasks. COP signals in the anterior-posterior (AP) and medio-lateral (ML) directions were recorded using a force platform during five 40-s trials of each task. We calculated total displacement and its standard deviation to evaluate COP movement and its variability, and the α exponent using detrended fluctuation analysis to evaluate complexity. During quiet standing, professional archers showed significantly lower variability in ML displacement. During aiming, they exhibited reduced total displacement in both AP and ML directions, lower variability in the AP direction, and reduced complexity in the AP direction compared to novices. These findings indicate that archery training enhances both the consistency and temporal regularity of postural control during aiming, suggesting that COP complexity provides novel insights into skill-specific balance adaptations.