Quantifying muscle contraction with a conductive electroactive polymer sensor: introduction to a novel surface...

Area of Science:

• Biomedical Engineering
• Wearable Technology
• Biomechanics

Background:

• Clinicians require precise methods to evaluate muscle contractility during physical activities for effective treatment planning.
• Surface mechanomyography (sMMG) offers a non-invasive approach to assess muscle function.

Purpose of the Study:

• To investigate the efficacy of a novel wearable conductive electroactive polymer sensor for quantifying muscle contractility.
• To assess the correlation between sMMG sensor data and established methods like electromyography (EMG) and dynamometry.

Main Methods:

• A wearable sMMG sensor utilizing a stretched dielectric elastomer to detect radial muscle displacement and quantify capacitance changes was developed.
• The sensor's performance was evaluated during parallel squat activities and isometric contractions, measuring muscle activation times.

Main Results:

• Strong correlations were observed between sMMG and EMG for muscle activation times in the quadriceps, hamstrings, and gastrocnemius during dynamic and isometric exercises.
• Moderate to strong correlations were found between sMMG-measured isometric muscle activation times and force output measured by a dynamometer.

Conclusions:

• The study supports the potential of electroactive polymer-based wearable sensors for accurate, non-invasive measurement of muscle contraction time.
• This technology could enhance clinical assessment of muscle function and guide rehabilitation strategies.