Motor Correlation Between Upper and Lower Limbs in a Throwing Task: The Effect of Fatigue and Distance

Abstract

Background: Coordination between the upper- and lower-limb joints is essential for accurate dart throwing; however, factors such as fatigue and throwing distance may influence this coordination. Objectives: This study aimed to determine whether throwing distance, mental fatigue, and muscular fatigue affect movement coordination between upper- and lower-limb joints during dart throwing. Methods: Twenty-eight university students (9 males and 19 females, aged 25 - 35 years) without regular dart-throwing experience participated. Dart throws were performed from two distances: the standard distance (2.37 m) and a challenging long distance (3.55 m), under three conditions: mental fatigue, muscular fatigue, and no fatigue. Movements were recorded using a three-dimensional motion analysis system. Mental fatigue was induced using a 70-minute Stroop task, and muscular fatigue was induced using a resistance-band dart-throwing protocol. Data were analyzed using a two-way repeated-measures analysis of variance (ANOVA; 3 fatigue conditions × 2 distances; P < 0.05). Results: A significant main effect of fatigue was observed for the shoulder-ankle pair (P = 0.032), with greater coordination under mental fatigue. Distance had significant effects on the elbow-ankle (P = 0.006) and wrist-ankle (P = 0.007) pairs, with greater coordination at the long distance. No significant effects were observed for the other joint pairs (P > 0.008), and no fatigue × distance interaction effect was observed (P > 0.012). Conclusions: Throwing distance and mental fatigue independently influenced upper–lower limb coordination in dart throwing, whereas muscular fatigue did not. These findings suggest that cognitive fatigue and task difficulty alter motor control strategies, with implications for training and performance in precision-based sports.