Abstract
INTRODUCTION: Conditioning involves the regulation of psychological health, physical fitness, and overall well-being, all of which are essential for optimal athletic performance. While psychological aspects have been extensively studied, the relationship between muscle activity and psychological factors such as anxiety and depression remains underexplored. METHODS: This study investigated the relationship between anxiety, depression, and forearm muscle activity in amateur athletes (mean age: 28 ± 9 years; sports experience: 13 ± 5 years) who participate in sports requiring upper extremity use. Muscle activity was evaluated using autocorrelation coefficients derived from muscle deformation data collected via a sensor array. Anxiety and depression levels were assessed using validated questionnaires, and their associations with muscle deformation were analyzed. RESULTS: Muscle deformation suggested a task-dependent relationship with psychological factors. A significant correlation was observed between anxiety and Hand tasks (r = -0.57, p = 0.004, pfdr = 0.05) and a trend was found between depression and random tasks such as HPI randomness (r = 0.46, p = 0.04, pfdr = 0.15). DISCUSSION: These findings suggest that chronic psychological stress may impair sustained muscle contraction during cyclic movements and promote fixed motor patterns during random tasks. This study elucidates how anxiety and depression affect muscle activity under different task conditions, providing a basis for optimizing training protocols and psychological stress management strategies in athletic conditioning.