We know that exercise alone has many benefits for our health that go beyond strengthening our muscles or promoting weight loss—from boosting energy levels to relieving stress to reducing the risk of a heart attack, we can better optimize our well-being by simply breaking a sweat. Previous research even says that working out can have significant effects on our health no matter what age we start hitting the gym.
However, a new study published in the journal Applied Physiology, Nutrition, and Metabolism, suggests that when it comes to exercising for brain health, intensity is everything.
During the experiment, researchers studied a sample of healthy older adults between the ages of 60 and 88 over a 12-week period and participated in three sessions per week. These older individuals were divided into three groups: One group participated in a HIIT workout (which consisted of four sets of high-intensity exercise on a treadmill for four minutes, followed by a recovery period) and another performed moderate-intensity continuous training (characterized by one set of moderate aerobic exercise for nearly 50 minutes). A third group participated in stretching only.
Then the researchers tested the amount of each group’s “newborn” neurons—this type of neuron has been previously shown to be more active than mature neurons and can better form new connections in the brain and create new memories. Scientists know that newborn neurons tend to be generated by exercise—the question becomes: Which exercise produces more of these neurons?
After analyzing these tests, they found that the seniors who participated in the HIIT workout improved their memory performance by 30%. The group who exercised moderately, on the other hand, saw no improvement.
These scientists found that the HIIT group specifically boosted their high-interference memory, which typically helps people distinguish between similar information (think differentiating cars from the same make or model).
This study can affect how we prevent diseases characterized by a decline in memory, such as dementia. If healthy older adults can boost their memory function with high-intensity workouts, exercise could become a viable (and relatively easy) way to prevent cognitive decline and promote healthy aging.
“There is urgent need for interventions that reduce dementia risk in healthy older adults. Only recently have we begun to appreciate the role that lifestyle plays, and the greatest modifying risk factor of all is physical activity,” lead author of the study Jennifer Heisz, Ph.D., notes.
In terms of what this means for how we should go about our exercise regimen, the researchers aren’t necessarily saying you should ditch your affinity for yoga in favor of a sweaty HIIT session. “It’s never too late to get the brain health benefits of being physically active, but if you are starting late and want to see results fast, our research suggests you may need to increase the intensity of your exercise,” says Heisz.
So if you would consider yourself to be newer to exercise, it may be worth it to start with more intense cardio rather than easing your way into a workout.
And adding intensity doesn’t necessarily mean opting for a flat-out run on the treadmill and possibly injuring yourself (especially if you’ve never tried a HIIT workout before!). Adding intensity can be as simple as venturing up hills on your daily walk or increasing your pace between street lamps, according to Heisz.
Although we aren’t sure what this research could mean for brains younger than the 60 to 88 age group, it sure has me wondering whether I should rethink my weekend barre ritual and convert to the HIIT craze. A workout that can last as little as five minutes and can boost memory function? It sure sounds enticing.