Increased heart stroke volume from intense exercise allows for greater delivery of fuel to muscles and the brain, enhancing cognitive functioning.

“As it does that, it delivers, because blood contains glucose and oxygen, and other things, it delivers more fuel to your muscles, which allows you to do yet more work per unit time. If you do this high-intensity-type training where your heart is beating very hard, so maybe the one-to-one ratio mile-run repeats that I described a minute ago, pretty soon, the stroke volume of your heart will really increase. As a consequence, you can deliver more fuel to your muscles and to your brain, your cognitive functioning will improve.”