A healthier heart equals a healthier brain — no surprise there — but what's the neuroscience behind the benefits of a cardio workout?

Cardiovascular exercise, be it a brisk stroll, a light jog, or an intense interval training session, releases neurotransmitters that can improve your mood, reduce stress, enhance your memory, and strengthen immunity.

In this episode of 'Your Brain On', we discuss:

• How your brain and your body respond to increasingly challenging aerobic workouts

• The neurochemistry of phenomena like 'feeling the burn' and 'runner's high'

• How the protein BDNF, triggered by exercise, can reverse the effects of aging and cognitive decline

• Ways to integrate more cardio exercise into your life, no matter which hurdles each day brings

We speak to Dr. John Ratey, author of 'Spark', widely celebrated as one of THE go-to books about how exercise benefits the brain. He shares the story that led him to write the book, about a school which favored fitness over sports skills in its PE classes and subsequently ranked amid the smartest schools in the world.

We're also joined by Dr. Art Kramer, Professor of Psychology and Director of the Center for Cognitive & Brain Health at Northeastern University, who dismisses the idea that you can be 'too old to exercise'.

And we invite anti-influencer and social media personality Erin Azar, AKA Mrs. Space Cadet, to the show, to talk about how her videos, which show the less glamorous side of running and exercise, went viral and spawned a community of nearly one-million followers.