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Related Experiment Video

Updated: May 14, 2026

Oscillation and Reaction Board Techniques for Estimating Inertial Properties of a Below-knee Prosthesis

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Published on: May 8, 2014

Joint impedance decreases during movement initiation.

Daniel Ludvig¹, Stephen A Antos, Eric J Perreault

¹Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, IL 60611 USA. daniel.ludvig@mail.mcgill.ca

Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference

|February 1, 2013

Summary

This summary is machine-generated.

Joint impedance decreases at movement initiation and increases upon cessation, even with rising muscle activity. This suggests the central nervous system independently controls joint impedance during movement.

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Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI

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Published on: April 18, 2011

Area of Science:

Neuroscience
Biomechanics
Human Motor Control

Background:

Joint mechanical properties, particularly impedance, are crucial for posture and movement control.
Previous research indicates joint impedance is lower during movement than during static posture.
Limited studies explore how joint impedance changes dynamically during transitions into and out of movement.

Purpose of the Study:

To investigate the dynamic changes in joint impedance during the transition from a postural task to a movement task.
To determine if changes in joint impedance correlate with muscle activation levels during movement initiation and cessation.

Main Methods:

Participants performed postural and movement tasks while joint impedance, torque, and electromyography (EMG) were measured.
Analysis focused on impedance variations during the initiation and cessation phases of movement.

Main Results:

Joint impedance significantly decreased at the onset of movement.
Joint impedance increased upon the cessation of movement.
These impedance changes occurred despite concurrent increases in torque and EMG levels.

Conclusions:

The central nervous system appears to modulate joint impedance independently of muscle activation during movement.
Findings suggest a distinct neural control mechanism for joint impedance during dynamic tasks.
This research offers new insights into the neural control of movement and posture.