Abstract
INTRODUCTION: Understanding foot joint loading during different dynamic activities is essential information for guiding exercise progression in rehabilitation. While walking and running biomechanics are well studied, joint-specific kinetic data during a single leg drop and hop task, often used in rehabilitation, are lacking. This study aimed to evaluate (1) the kinetic behavior of the ankle, Chopart, Lisfranc, and MTP-1 joints during a drop-hop task under different visual constraints and (2) to contextualize these findings by comparing them with heel-strike running, to assess the relative loading demands of the drop-hop task. METHODS: Seventeen recreationally active male adults performed a single-leg drop and hop under two visual focus conditions: central (focusing on the landing spot) and peripheral (focusing straight ahead). Kinematics, moments, and power were analyzed using a four-segment foot model with statistical parametric mapping. Additionally, peak plantarflexion moments and power outputs were compared with existing data from heel-strike running data from a mixed-sex sample (4 males, 3 females) collected in a separate study using the same setup. RESULTS: Findings revealed no differences between central and peripheral focus conditions. Heel-strike running shows similar joint loading, but higher power generation (p < 0.001) at the ankle and Chopart joint, higher absorption (p < 0.001) at the Chopart and MTP-1 (p < 0.05) joint and lower power absorption (p < 0.001) at the ankle and Lisfranc joint. CONCLUSION: Visual input does not influence foot biomechanics during a single-leg drop and hop. This task produces similar joint loading patterns similar to heel-strike running but with reduced power generation at the ankle and midfoot. Contrary to global belief, the single leg drop-hop task is not excessively more demanding in terms of foot joint loading, supporting the earlier use of drop-hop exercises in rehabilitation programs. They offer a controlled way to reintroduce loading while avoiding the full propulsion demands of running, independent of visual focus.