The influence of mood during treadmill running on biomechanical asymmetry of the lower-limbs

This study aimed to investigate if mood effects lower-limb biomechanical asymmetry during running. Twenty runners (13M, 7F; age 22-58 years), performed four 3-minute runs at their 5km pace (3.3 ± 0.3 m/s), preceded by a mood questionnaire. Baseline data were captured, followed by randomised mood conditions: anger, happiness, and sadness; elicited with film clips and music. Symmetry angles used for analysis. In the sadness condition, compared with baseline, biomechanical asymmetry significantly increased (p < .05) by 3.7% at ground contact for hip abduction, and at toe-off for knee abduction by 0.6% and internal rotation by 1.1%. Toe-off plantarflexion asymmetry decreased by 2.2% with anger, compared to baseline. Happiness did not appear to affect asymmetry. Results suggest sadness may increase asymmetry and associated overuse injury risk, and anger may facilitate symmetry.