Objectivity and validity of EMG method in estimating anaerobic threshold

Area of Science:

• Exercise Physiology
• Sports Science
• Biomedical Engineering

Background:

• Accurate determination of anaerobic threshold (AT) is crucial for optimizing exercise intensity and training.
• Traditional methods like ventilatory threshold (VT) rely on gas exchange measurements.
• Electromyography (EMG) offers a potential alternative for assessing muscle fatigue and AT.

Purpose of the Study:

• To compare the performance of anaerobic threshold (AT) point estimates using different filtering intervals (9-30s).
• To investigate the relationship between AT estimates derived from EMG and VT methods.
• To evaluate the validity and reliability of an EMG-based AT estimation procedure.

Main Methods:

• Incremental cycle ergometer exercise was performed by 69 untrained male university students.
• Anaerobic threshold (AT) was estimated using both ventilatory threshold (VT) via V-slope method and electromyographic (EMG) activity.
• EMG signals were analyzed using various filtering intervals (9, 15, 20, 25, 30s) and a Matlab-based computing procedure.

Main Results:

• EMG-derived AT estimates showed greater consistency across different filtering intervals compared to VT estimates.
• EMG-derived AT values demonstrated higher inter-correlations among themselves than VT-derived values.
• The Matlab-based EMG analysis procedure yielded highly correlated and nearly identical values to VT estimates.

Conclusions:

• EMG signals provide a valid and reliable alternative for estimating anaerobic threshold (AT) during incremental exercise.
• The proposed EMG signal analysis method, implemented in Matlab, is a promising tool for AT assessment.
• EMG offers a new option for researchers and clinicians in exercise physiology and sports science.