Changes in cortical activity measured with EEG during a high-intensity cycling exercise

Area of Science:

• Exercise Physiology
• Neuroscience
• Sports Science

Background:

• Understanding the neurophysiological underpinnings of fatigue during intense exercise is crucial for optimizing performance.
• Electroencephalography (EEG) offers a non-invasive method to measure brain activity during physical exertion.

Purpose of the Study:

• To investigate the effects of high-intensity cycling exercise on spectral and temporal aspects of EEG.
• To identify changes in electrocortical activity associated with the development of fatigue during cycling.

Main Methods:

• 10 experienced cyclists underwent a maximal aerobic power test and a time-to-exhaustion trial at 85% maximum power.
• A 64-channel EEG system recorded brain activity at 500 Hz.
• Independent Component Analysis (ICA) and time-frequency analysis were used to examine EEG data.

Main Results:

• Significant increases in EEG power were observed as fatigue developed, most notably in the frontal cortex.
• Changes in electrocortical activity were detected in frontal, supplementary motor, and parietal areas.
• Event-related desynchronization in the supplementary motor area correlated with pedaling mechanics and force production onset.

Conclusions:

• The cerebral cortex plays a significant role in high-intensity cycling tasks.
• EEG findings suggest involvement of executive control, motor planning, and execution during fatiguing cycling.
• Increased frontal EEG power indicates heightened cognitive demands or regulatory processes during exercise-induced fatigue.