Table of Contents

ABSTRACT

Background: The central-governor model putatively explains the mechanism of endurance exercise-induced central-fatigue, however, high-intensity exercise-induced central-fatigue strategies have not been investigated yet. This study aimed to examine how central fatigue affects neural response alterations, as measured by electro-encephalographic (EEG) recordings, in intermittent high-intensity cycling. Methods: Neural responses were assessed by measuring the alteration of brainwaves based on spectral energy band estimates during an intermittent, high-intensity, 60-minute exercise-bout on a cycle ergometer. The cycle ergometer incline was changed every 10 minutes in an intermittent pattern (10-20-5-20-5-10 degrees). EEG was used to analyze altering brain function. Heart rate (HR), blood lactate (BL), and rating of perceived exertion (RPE) were measured after the participants completed each change in incline. Results: The results showed that HR, BL, and RPE increased at an incline of 20 degrees in comparison to a 5-degree incline. The spectral power of EEG was significantly increased (P ˂ 0.01) in the alpha and beta frequency ranges with a change in inclines between 5 and 20 degrees. The spectral power of the EEG was significantly increased (P ˂ 0.01) over the whole frequency range from rest (theta: +251%, alpha: +165%, beta: +145%). Conclusion: Higher, relative, intensities (10 and 20 degrees) increased brain function, regardless of fatigue occurrence. HIIT (high-intensity interval training) led to an alteration in the neural response. Further work investigating the usefulness of HIIT to improve brain function is warranted.

Keywords: high-intensity interval training, EEG, central-fatigue, cycling training