Physical fitness influences cognitive function by enhancing blood flow and oxygen delivery to the brain, which can improve memory and learning abilities. Regular physical activity has been linked to increased levels of neurotransmitters like serotonin and dopamine, which support mood regulation and cognitive processes. Exercise also promotes neurogenesis, the growth of new brain cells, and reduces the risk of cognitive decline and diseases like Alzheimer's. Thus, maintaining a fit lifestyle contributes to both physical and mental well-being.