Figure 1.

Schematic summarizing proposed mechanisms by which exercise training may alter brain structure and function as well as lower the risk of brain-related dysfunction and disease via alterations in systemic function. BDNF, brain-derived neurotrophic factor; CBF, cerebral blood flow; CO₂, carbon dioxide; eNOS, endothelial nitric oxide synthase; IGF-1, insulin-like growth factor 1; MAP, mean arterial blood pressure; NO, nitric oxide; PGC-1α, peroxisome proliferator-activated receptor-γ coactivator; ROS, reactive oxygen species; RNS, reactive nitrogen species; VEGF, vascular endothelial growth factor.