Just A 6-Minute HIIT Workout Can Give You A Brain Boost

Everyone knows that exercise in any form has a ton of health benefits for the body, like improving heart health, reducing the risk of diseases such as diabetes, and keeping your bones and muscles strong. But exercise can also help your brain by boosting mental health, improving sleep, and even lowering risk of dementia and Alzheimer’s disease. And you don’t have to hit the gym for hours to see these results. Short, intense bursts of exercise are enough to reap major brain benefits, according to a recent study.

For the study, participants engaged in light cycling for 90 minutes, and then after a few minutes of rest, six minutes of high-intensity interval training (HIIT). After each of the two workouts, researchers measured participants’ body levels of a protein called “brain-derived neurotrophic factor,” or BDNF, which many scientists believe is important for healthy brain function and neuroplasticity. “Some people describe it as brain fertilizer,” says Travis Gibbons, Ph.D., a postdoctoral physiology researcher at the University of British Columbia and a researcher on the study.

After 90 minutes of light cycling, the participants showed slightly higher BDNF levels. But after just six minutes of high-intensity exercise — in this case, 40 seconds of rapid, intense cycling followed by 20 seconds of light cycling, repeated six times in a row — BDNF levels shot up by four to five times more than it did after the 90-minute workout. The researchers published the study last month in The Journal of Physiology.

One potential theory to explain these results is that our bodies might produce BDNF when under stress — and even a short period of high-intensity interval exercise could create more stress than light exercise for 90 minutes.

The researchers didn’t look at how BDNF affected the participants’ brain function, but in animal models, BDNF has been shown to support neuroplasticity and neuron growth. In addition, low BDNF levels have been associated with neurological diseases such as Parkinson’s.

“We know that exercise is good for brain health — it delays the onset of neurodegeneration, it can be good for cognitive function” Gibbons says. Although BDNF may not explain all of that benefit, it’s probably one of the factors, he adds.

“When we start to elucidate the mechanisms by which exercise is good for the brain, we can start to better understand how to exercise most efficiently in order to specifically target brain health,” Gibbons says.

HIIT workouts have become popular for plenty of other reasons though. For one, they’re efficient. Not everyone has time to spend an hour in the gym every day, and HIIT boosts fitness in a much shorter amount of time per day than other workouts do. In addition, interval training has been shown to reduce body fat and improve cardiovascular health.

If you want to give HIIT a try, potential workouts include:

• Sprinting down the block for a minute, then jogging back to the start and sprinting again
• Cycling as fast as you can followed by light pedaling, like the participants in the study
• Doing bodyweight workouts like jumping jacks, burpees, or high-knees as fast as you can, followed by a short, active recovery period
• Lifting weights in intense bursts, with short breaks in between sets

Although HIIT workouts don’t need to last very long, the goal is to push yourself while you’re doing them — so you should work hard during the set, at a pace that you couldn’t keep up for an extended period of time. But exactly what that means, and how you go about it, can be up to you.

“I don’t think it has to be too structured,” Gibbons says. “It can be just worked in wherever you can.”

If you absolutely hate HIIT, don’t worry though. Another recent study found that exercising as little as one to four days per month is linked to higher cognitive performance, verbal memory, and processing speed at age 69 — as long as you do it consistently. So you don’t have to exercise often, and it doesn’t have the be HIIT, to reap the brain benefits of exercise.