Single Leg Drop and Hop: Insight Into Multisegment Foot Kinematics, Kinetics and the Role of Visual Focus in Healthy Young Adult Males

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.

Keywords: joint power; motor control; proprioception; visual input.

FIGURE 1

(A) Figure showing the marker placement with assumed rigid segments, anatomical landmarks and frames associated to the IOR‐4 Segment‐model used in the present study. Transverse planes (dash–dot triangles) and X‐ and Z‐axes (solid arrows) on these planes are shown. (B) Drop and hop with the red box representing the central visual focus and the black box representing the peripheral visual focus.

FIGURE 2

Joint kinematics in three planes: Sagittal (DF = dorsiflexion/PF = plantar flexion), Frontal (Inv = inversion/Eve = eversion) and Transverse (Add = adduction/Abd = abduction). Data of the peripheral visual focus are represented by a red line. Data of the central visual focus are shown with a black line.

FIGURE 3

Internal joint moments in three planes: Sagittal (DF = dorsiflexion/PF = plantar flexion), Frontal (Inv = inversion/Eve = eversion) and Transverse (Add = adduction/Abd = abduction). Data of the peripheral visual focus are represented by a red line. Data of the central visual focus are shown by a black line.

FIGURE 4

Joint powers in three planes: Sagittal (PF = plantar flexion/DF = dorsiflexion), Frontal (EV = eversion/Inv = inversion) and Transverse (Abd = abduction/Add = adduction). Data of the peripheral visual focus are represented by a red line. Data of the central visual focus are shown by a black line.

FIGURE 5

Bar chart visualizing the internal joint moments and power in the sagittal plane, comparing both single leg drop and hop tasks (light green: peripheral visual focus and dark green: central visual focus) with heel‐strike running (gray). *p < 0.05, **p < 0.01, ***p < 0.001.