Related Experiment Video
Updated: Oct 28, 2025
Lower Limb Biomechanical Analysis of Healthy Participants
Published on: April 15, 2020
Responses in knee joint muscle activation patterns to different perturbations during gait in healthy subjects
Jim C Schrijvers1, Josien C van den Noort2, Martin van der Esch3
1Amsterdam UMC, Vrije Universiteit Amsterdam, Department of rehabilitation medicine, Amsterdam Movement Sciences, de Boelelaan 1117, Amsterdam, The Netherlands.
Purpose:
To compare the responses in knee joint muscle activation patterns to different perturbations during gait in healthy subjects.
Scope:
Nine healthy participants were subjected to perturbed walking on a split-belt treadmill. Four perturbation types were applied, each at five intensities. The activations of seven muscles surrounding the knee were measured using surface EMG. The responses in muscle activation were expressed by calculating mean, peak, co-contraction (CCI) and perturbation responses (PR) values. PR captures the responses relative to unperturbed gait. Statistical parametric mapping analysis was used to compare the muscle activation patterns between conditions.
Results:
Perturbations evoked only small responses in muscle activation, though higher perturbation intensities yielded a higher mean activation in five muscles, as well as higher PR. Different types of perturbation led to different responses in the rectus femoris, medial gastrocnemius and lateral gastrocnemius. The participants had lower CCI just before perturbation compared to the same phase of unperturbed gait.
Conclusions:
Healthy participants respond to different perturbations during gait with small adaptations in their knee joint muscle activation patterns. This study provides insights in how the muscles are activated to stabilize the knee when challenged. Furthermore it could guide future studies in determining aberrant muscle activation in patients with knee disorders.
