Is Swimming Training Experience Associated with Better Sensorimotor Control in Water? An Exploratory Study of Upper-Limb Joint Position Sense, EEG Activity, and Subjective Workload

Background/Objectives: This study examined whether swimming experience is associated with better sensorimotor control in water by comparing joint position sense, cortical activity, and subjective workload across training backgrounds and environments. Methods: Thirty-six participants (12 swimmers, 12 Chinese Wushu (Wushu) athletes, and 12 untrained individuals) performed continuous shoulder and elbow joint-position-reproduction tasks on land and in water. Joint-angle errors, resting-state and task-related α- and β-band EEG power, and NASA Task Load Index scores were assessed using cluster-based permutation tests and mixed analyses of variance with multiple-comparison correction. Results: Environment affected left-elbow absolute error (p = 0.0015) and constant error at all four joints (all corrected p ≤ 0.0028), without a swimming-specific accuracy advantage. Wushu athletes had lower signed left-shoulder and left-elbow constant errors than swimmers. Swimmers showed a greater water–land increase in resting-state α power than untrained participants before right-side tasks (Holm-adjusted p = 0.0048). Task-related α desynchronization was weaker in water during left-shoulder and left-elbow tasks; no corrected training-related effects emerged for task-related α or β power. Physical demand and perceived performance showed group × environment interactions (both corrected p = 0.0458); swimmers reported lower physical demand than untrained participants in water. Conclusions: Swimming experience was associated with distinct pre-task resting-state α responses, but not better joint-position accuracy or distinct task-related cortical activity modulation. Long-term training in different environments appeared to reduce the physical demand of sensorimotor tasks performed in the familiar environment. These findings provide limited support for swimming-specific sensorimotor advantages in water.