Study links two types of exercise with 'substantial' brain benefits

Many people are taking supplements that claim to boost brain plasticity, but a new study out of Australia has found that partaking in one of two different types of workouts — or both, if you're particularly energetic — may be more effective. In addition to identifying two beneficial types of exercise, the study also found that a different type of activity may block the brain benefits by increasing cortisol, the stress hormone.

Brain plasticity, also called neuroplasticity, refers to the brain's ability to adapt and change. Though it was once believed that brain plasticity disappeared in adulthood, years of modern research has challenged that belief. A number of supplements are alleged to improve brain plasticity, though evidence may be slim in many cases. Exercise, however, may be a safe and more effective alternative that helps the brain to tweak its neural connections.

Researchers with the University of South Australia conducted their study with 128 people and found that it took only 25 minutes of moderate-intensity continuous aerobic exercise or 20 minutes of interval training to boost neuroplasticity. The findings build upon existing research that indicates aerobic exercise has positive effects on cognition.

The stress hormone cortisol may have a negative effect on neuroplasticity related to exercise, however, by blocking the beneficial response, according to the study. For this reason, engaging in high-intensity activity for a long period of time rather than in short intervals may eliminate the positive effect seen in interval training.

In the cases where benefits were observed, the study's participants were tasked with keeping their heart rate at between 50-percent and 90-percent intensity levels. Examples of this type of exercise could include moderate-intensity cycling or running at a high intensity in brief spurts broken up with periods of rest, a method that helps keep cortisol levels in check.