Breathing Control in Exercise

Despite more than a century of research on the mechanisms of exercise hyperpnea, we are still unable to account for the fundamental coupling or link between the magnitude and kinetics of the ventilatory response to exercise and those of the pulmonary gas exchange. Such a coupling prevents arterial PCO₂ to rise, when CO₂ production increases during a physical activity. This chapter presents the challenges of understanding the regulation of respiration in exercising humans in keeping with the impressive mass of studies published on this subject. Indeed, the search for the mechanisms responsible for the isocapnic response to a muscular exercise in humans has led to the production of the most creative and rich literature in the field of breathing control; there is however no current understanding on how alveolar ventilation can adjust to a rapid change in level of metabolism, in turn maintaining arterial blood gas homeostasis.