BDNF (Brain-Derived Neurotrophic Factor)
A protein that supports the survival, growth, and maintenance of neurons. BDNF is essential for hippocampal neurogenesis -- the creation of new neurons in the brain region most critical for memory. Levels decline with age. Aerobic exercise is one of the most potent known stimulators of BDNF production, operating through a lactate-driven pathway that activates its expression in the hippocampus. Low BDNF is associated with accelerated hippocampal atrophy and increased risk of depression.