Design Validation of a Low-Cost EMG Sensor Compared to a Commercial-Based System for Measuring Muscle Activity and...

Area of Science:

• Biomedical Engineering
• Neuroscience
• Sports Science

Background:

• Electromyography (EMG) sensors are crucial for diagnosing neuromuscular disorders and measuring muscle activity.
• Commercial EMG systems are often prohibitively expensive and inaccessible for widespread individual use.
• There is a need for validated, low-cost EMG solutions for research and clinical applications.

Purpose of the Study:

• To validate a newly designed low-cost EMG sensor against a commercial system.
• To assess the sensor's capability in measuring muscle activity and fatigue.
• To determine the reliability and agreement between the developed and commercial EMG systems.

Main Methods:

• A low-cost EMG sensor and a commercial system were concurrently used to record signals from the vastus lateralis muscle during maximum voluntary contractions (MVC).
• Signal analysis involved Spearman's correlation and intra-class cross-correlation (ICC) using SPSS 26.0.
• Muscle fatigue was assessed using time-domain (RMS, MAV) and frequency-domain (MNF) indicators.

Main Results:

• Excellent relative agreement was observed between the low-cost sensor and the commercial system, with ICC values ranging from 0.65 to 0.92.
• Spearman's correlation coefficients averaged 0.76 at peak contraction and 0.71 at mean contraction.
• The low-cost sensor accurately reflected muscle fatigue, showing increasing RMS and MAV values and a decreasing MNF in the time and frequency domains, respectively.

Conclusions:

• The designed low-cost EMG sensor demonstrates good to excellent agreement with a commercial system, confirming its reliability.
• The sensor is suitable for accurate muscle fatigue assessment.
• This affordable EMG solution has potential applications in rehabilitation, sports science, and ergonomics.