Altered Neural Response Induced by Central-Fatigue in the Cortical Area During High-intensity Interval Pedaling

Introduction: The central-governor model explains the mechanism of endurance exercise-induced central fatigue, but high-intensity exercise-induced central fatigue has not been investigated yet. This study aimed to research how central fatigue during high-intensity intermittent pedaling alters the neural response, which results in electroencephalography (EEG) recordings. Methods: We assessed neural response by measuring the alternation of brainwave spectral power during an intermittent high-intensity 60-minute exercise on an ergometer cycle. The cadences were changed every 10 minutes according to intermittent pattern altering (90-120-60-120-60-90 rpm). EEG was used to analyze altering brain function. Heart rate (HR), blood lactate (BL), and rating of perceived exertion (RPE) were measured after the change in cadences. Results: HR, BL, and RPE increased at a cadence of 120 rpm compared with 60 rpm on the ergometer cycle. The spectral power of EEG, according to cadence × brainwaves, significantly increased (P˂0.01) in the alpha and beta frequency ranges with a change in cadences between 60 rpm and 120 rpm. The spectral power of the EEG significantly increased (P˂0.01) over the whole frequency range from rest to warming (theta: 251%, alpha: 165%, beta: 145%) and significantly reduced in theta, alpha, and beta (theta: 176%, alpha: 142%, beta: 77%) (P≤0.01). Conclusion: High-intensity exercises (90 and 120 cadences) increased brain function, regardless of fatigue occurrence. High-intensity interval training (HIIT) led to altering the neural response. It would be required to investigate the usefulness of HIIT to treat some of the psychotic disorders.