Wavelet Analysis of Physiological Control Mechanisms during Physical Activity

In exercise physiology, a novel model based on the regulation of neural effort and fatigue has been recently proposed. This model theorizes that physical activity is controlled by a central regulator in the brain, and the human body works as a complex integral system, unlike the Cardiovascular/Anaerobic/Catastrophe model of Sir A. V. Hill of exercise physiology. In this study, physiological data were collected from club-level cyclists for different types of pacing that were self pace, even pace, and variable pace for a 20-km cycling time trial. These physiological data were analysed to assess the underlying system control mechanisms that show how the central regulator paces the human body during exercise. Continuous Wavelet Transform (CWT) was used to analyse the non-stationary physiological signals that were heart rate (HR/bpm) and rate of volume of oxygen consumption rate (VO2/ Lmin-1). Normalised mean wavelet powers were used to compare the powers at different frequency bands of the continuous wavelet spectrum. These frequency bands were classified as High Frequency (HF), Low Frequency (LF) and Ultra Low Frequency (ULF) bands. There was a significant difference in the ULF band for the rate of volume of oxygen consumption (p