Cerebrovascular responses to exercise

Abstract

Abstract Various studies have linked exercise to brain structure and function, but the mechanistic pathways underlying exercise-induced benefits are poorly understood. Augmented brain function is related to cerebrovascular responses to exercise in adults; however, evidence in children is limited. This is an emerging area of integrative paediatric exercise physiology and this chapter provides insight into the development of cerebral metabolism and blood flow, key mechanisms that regulate cerebral blood flow at rest, and responses to exercise. Similar to adults, the cerebral blood flow response to incremental exercise to exhaustion in children and adolescents is biphasic, increasing up to the ventilatory threshold, then declining back to resting values from the respiratory compensation point to maximum. In contrast, the amplitude of the increase in cerebral blood velocity is about half of that noted in adults. Unlike adults, the biphasic response in cerebral blood flow is not mirrored by end-tidal carbon dioxide partial pressure (PETCO2), and the cerebral blood flow–ventilation relationship differs, suggesting underlying exercise regulatory pathways are developmentally distinct. The paucity of evidence on acute and chronic cerebrovascular responses to physical activity and exercise training in the child or adolescent means the true impact of exercise on brain structure and function and future brain health has yet to be fully understood.