New research shows that mitochondria can influence cells in distant organs. For example, exercise that improves mitochondria in skeletal muscles can also positively affect the brain, heart, and lungs. This suggests localized mitochondrial interventions can have widespread systemic benefits.

Dr. Wendy Suzuki explains a profound long-term benefit of exercise: it promotes the growth of brand new brain cells in the hippocampus, the brain's center for long-term memory. This process, called neurogenesis, builds a bigger, more resilient hippocampus, helping to protect memory function as you age.

Physical activity stimulates the release of Brain-Derived Neurotrophic Factor (BDNF), crucial for neuron growth, via two mechanisms. Muscles release a protein (a myokine) and the liver, in response to exercise stress, releases a ketone (beta-hydroxybutyrate). Both cross the blood-brain barrier to stimulate BDNF production.

The cognitive benefits of exercise can be transmitted molecularly. In lab studies, blood from exercised mice, when transfused into sedentary mice, conferred the same improvements in brain function. This proves specific blood-borne factors, not just physical activity, are at play.

The cognitive benefits of exercise are partly driven by organ-to-organ communication. Research shows physical activity prompts the liver to release specific factors, such as the protein clusterin, which then travel through the blood to the brain and enhance its function.

While BDNF is associated with exercise's brain benefits, the BDNF produced in muscles doesn't readily cross into the brain. Instead, lactate produced during intense exercise enters the brain and acts as a signaling molecule, stimulating local BDNF production and improving hippocampal function.

Studies comparing workout intensities found that only high-intensity exercise significantly increased plasma serotonin. Dr. Patrick explains this is crucial because serotonin plays a key role in impulse control, helping to filter out modern-day distractions and maintain focus.

Each workout releases a cocktail of neurochemicals, including dopamine, serotonin, and the growth factor BDNF. This "bubble bath" for the brain directly stimulates the growth of new cells in the hippocampus, making it larger and more resilient, which improves long-term memory and can delay dementia.

Beyond cardiovascular benefits, physical exercise, particularly load-bearing activities like running or weightlifting, triggers bones to release a hormone called osteocalcin. This hormone travels to the brain's hippocampus, enhancing its function and supporting the formation of new memories.