Imagine burning 30 percent more calories in half the amount of time you usually spend working out—and continuing to burn calories after the workout ends. High-intensity interval exercise (HIIE)—a type of workout that alternates bursts of intense cardiovascular exercise with brief breaks—does just that. A recent study from Brazil suggests that HIIE does good for our bodies beyond calorie burning—doing just one HIIE workout can help protect our brains from potentially dangerous free radicals.
Free radicals are oxygen-containing molecules that have an uneven number of electrons—subatomic particles that contain an electrical charge. Our bodies naturally produce free radicals during exercise, but their electrons can interact with other molecules and cause damage in the cells through a reaction called oxidation. Our bodies contain molecules called antioxidants and we can gain more through diet. Antioxidants defend against the harmful effects of free radicals. However, if we have more free radicals than antioxidants, we can develop oxidative stress where tissues, proteins and even DNA can become damaged.
The Brazilian study looked at rats that ran on treadmills for one minute, with brief recovery periods between runs. Just one day after the exercise sessions, the rats showed higher levels of antioxidant enzymes in the parts of the brain associated with memory, learning and emotions. Antioxidant enzymes break down harmful free radicals, which means there’s less chance of oxidative stress. There was also an increase in the level of nonenzymatic antioxidant capacity—this means more antioxidant molecules circulate to fight the free radicals that weren’t already destroyed.
If burning more calories or working out for less time hasn’t been enough to get you to do a HIIE workout, consider trying it just once. Your brain might think it’s a good idea.
Gina Mantica is a PhD candidate in biology at Tufts University. Her thesis work in the lab of Mimi Kao, PhD, focuses on how the basal ganglia, a part of the brain important for the coordination of movement, affects behavioral variability. This research will help in better understanding basal ganglia disorders, like Parkinson’s disease, that result in abnormal motor variabilities.