Exercise For The Brain

We often talk about the benefits of exercise in physical terms; building lean muscle or increasing stamina make it easier to carry out everyday activities like climbing the stairs or running for the bus. The connection between exercise and the brain, however, is less clear.

- Alice Ball

When it comes to the brain-benefits of exercise, we might vaguely throw around the terms ‘endorphin rush’ or ‘runner’s high’, but what do they really mean? And is it possible for even the biggest fitness-phobe to achieve one?

First things first, the so-called runner’s high is real, and even if pounding the pavements isn’t your thing, non-runners can still experience this sense of elation after a workout. Any exercise puts the body under stress and pain; and since the 1970s, it’s been assumed that the body’s response to exercise-induced stress is to trigger the release of endorphins — neurotransmitters produced by the brain’s hypothalamus and pituitary gland. Endorphins are structurally similar to the drug morphine and have similar opiate effects in relieving pain and boosting feelings of pleasure and euphoria.

But Dr Michael Mosley, TV presenter and science journalist, told Optimum Nutrition that while studies show endorphin levels in the blood spike after exercise, there is one major “incompletion” in the hypothesis. Endorphin molecules are too big to cross the blood-brain barrier, meaning it’s unlikely that they have a direct effect on brain function during exercise.

“Instead, there is mounting evidence for the importance of endocannabinoids (eCBs) when it comes to explaining the athlete’s ‘high’,” he said.

“Endocannabinoids are produced throughout the body and have many functions. As well as making you feel good they reduce inflammation and increase insulin sensitivity, affecting fat and energy metabolism.”