Impacts of emotional priming during multiple object tracking tasks on drop landing strategy in individuals with functional ankle instability: an exploratory study

Attentional resources play a critical role in voluntary movement execution under dual-task (DT) conditions, such as Multiple Object Tracking (MOT). Efficient resource allocation requires cognitive adjustments, which may divert attention from motor control and exacerbate movement deficits. Functional Ankle Instability (FAI) is characterized by impaired proprioception, neuromuscular dysfunction and compromised motor strategy, often resulting in inefficient landing strategies. While emotional priming has been shown to influence cognitive and motor performance, its specific impact on drop landing strategies in FAI individuals during cognitively demanding tasks remains unclear. This study aims to examine how different emotional priming conditions influence the biomechanical characteristics of drop landing strategies in individuals with FAI while performing an MOT task. Fourteen individuals with FAI and fourteen matched healthy controls participated in a drop landing experiment under dual-task (MOT) and single-task conditions. Three emotional states—Neutral Emotion (NEm), Negative Emotion (NEg), and Positive Emotion (PE)—were induced through priming. Kinematic and kinetic data were collected using a Vicon motion capture system and a Kistler force plate. A 2 × 2 × 3 mixed-design ANOVA was conducted to assess the effects of group, task conditions, and emotional state. Significant interaction effects between task condition and group were observed, especially in hip flexion at Initial Contact (IC) and knee stiffness. Under DT conditions, individuals with FAI demonstrated reduced hip flexion ( p = 0.001) and increased knee stiffness ( p = 0.004), indicating a rigid landing pattern. Emotional priming interacted with task condition to modulate joint kinematics and kinetics. Specifically, under DT conditions, PE enhanced ankle plantarflexion ( p = 0.002) and reduced knee flexion at IC ( p = 0.018), while NEm reduced hip flexion at peak Vertical Ground Reaction Force (VGRF) ( p = 0.016) and increased hip stiffness ( p = 0.044). In particular, following a significant three-way interaction, simple-simple effect analyses revealed that for individuals with FAI under dual-task landing, peak VGRF in the NEm condition was significantly higher than in the PE condition ( p = 0.038). Under the same dual-task condition, lower extremity stiffness in the NEm condition differed significantly from both the PE ( p = 0.033) and NEg ( p = 0.022) conditions, while hip energy absorption in the NEm condition differed significantly only from the NEg condition ( p = 0.038). Additionally, within the NEm condition, hip energy absorption was significantly greater during dual-task landing than during single-task landing ( p = 0.039). Dual-tasking elicits a more rigid landing strategy in individuals with FAI, marked by elevated knee stiffness and reduced hip flexion. Emotional priming further modulates these dual-task-related biomechanical alterations. Compared with the NEm condition, both PE and NEg conditions attenuated selected indicators of landing rigidity; the PE condition additionally decreased peak VGRF, whereas the NEg condition reduced hip energy absorption. These effects appeared to occur through distinct biomechanical pathways, with PE primarily influencing impact loading and NEg influencing proximal mechanical contribution. These findings provide preliminary evidence that emotional modulation may influence landing biomechanics under cognitive load and may have implications for injury prevention strategies in individuals with FAI.