Using an Electromyography Method While Measuring Oxygen Uptake to Appreciate Physical Exercise Intensity in...

Area of Science:

• Exercise Physiology
• Sports Science
• Biomedical Engineering

Background:

• Muscle fiber electrical signals diminish during exercise due to contractions, influenced by energy availability and chemical mediators.
• Reduced adenosine triphosphate (ATP) production negatively affects muscle activation rates, crucial for athletic performance.
• Current training intensity monitoring using heart rate may not fully correlate with muscle activation and lactate accumulation.

Purpose of the Study:

• To investigate the relationship between muscle activation rate, exercise intensity, and physiological markers in athletes.
• To analyze how age and power output affect electromyography (EMG) signals, including electromyography fatigue threshold (EMG_FT) and electromyography maximum reached point (EMG_MRP).
• To explore the correlation between EMG measures and ventilatory thresholds (VT1 and VT2).

Main Methods:

• A 4-month prospective analytical study involving 30 participants.
• Incremental exercise bike tests were conducted to measure maximum aerobic capacity.
• Muscle activation rate in the vastus lateralis was measured using electromyography (EMG).

Main Results:

• EMG signal, EMG_FT, and EMG_MRP decreased with age, while power output increased.
• Higher power output correlated with lower EMG_FT and EMG_MRP.
• Increased power output was observed across aerobic, mixed, and anaerobic exercise zones.

Conclusions:

• A significant relationship exists between aerobic/anaerobic ventilatory thresholds (VT1/VT2) and EMG_FT/EMG_MRP, respectively.
• Changes in oxygen uptake positively influenced power output at EMG_FT and EMG_MRP, enhancing performance.
• EMG measures provide valuable insights into exercise intensity and performance, aligning with ventilatory thresholds.