The Exercise Routine That Can Improve Your Memory

Exercise is good for so many aspects of mental and physical wellbeing — and a new a study recently discovered that it can give your memory a boost, too.

Research conducted at McMaster University, and published in the Journal of Cognitive Neuroscience, found that just 20 minutes of exercise three times a week, over a six-week period, improved memory function in study participants.

Exercise is believed to lower one’s risk of developing Alzheimer’s disease and dementia, and this study suggests that even a small amount of exercise could make a difference in memory function.

The study

In the study, 95 people who hadn’t been exercising were assigned to three groups. One group did six weeks of exercise, another did six weeks of exercise plus brain-training activities, and a third group continued as normal, not exercising at all. The participants underwent a memory test before and after the study; they were shown numerous images and had to recall if they’d seen them before.

Members of both groups who exercised showed improvement on the memory test after six weeks, increasing their scores by more than 10%, according to Jennifer Heisz, lead researcher of the study and an assistant professor of kinesiology at McMaster. While some individuals who performed brain training activities on top of the exercise had an even greater benefit, overall there was little difference between the exercise and the exercise-plus-brain-teaser group.

Why does exercise improve memory function?

It’s not clear exactly how exercise boosts memory, but it has been shown that physical activity results in more brain-derived neurotrophic factor (BDNF), a protein found in the brain. The protein is “like a fertilizer for the cells,” says Heisz. “The more that’s available in the brain, the more enriched the cells are, and the better they are able to survive and function.”

The study involved alternating bouts of high-intensity and low-intensity aerobic exercise, as previous? studies have shown that more BDNF is released with this kind of exercise. “We thought we’d hit it with a sledgehammer,” says Heisz with a laugh.

The participants, who ranged between 17 and 30 years old, underwent fitness tests to determine their peak heart rate levels. Their exercise routines consisted of one minute of intense spinning on a stationary cycle, bringing them to within 90% to 95% of their peak heart rate, followed by one minute of slow cycling. The high-to-low-intensity cycle was repeated 10 times. “This intermittent exercise – punching it and backing off – is the most effective at releasing this fertilizer,” explains Heisz.

Try it at home

In the study, peak heart rate was calculated using a treadmill stress test, but a “quick and dirty” way of figuring out peak heart rate is to subtract your age from 220. (For example, a 40-year-old would have a peak heart rate of 180.) The formula, though, doesn’t work well for people taking certain medications that affect heart rate, such as blood pressure medications. Another way of achieving peak heart rate is to simply “push yourself hard,” says Heisz.

Even if you’re not currently active, 20 minutes of fluctuating high-intensity and low-intensity exercise is a good starter routine, one that's been shown to be well-tolerated by sedentary people, Heisz says, and one that can be fun, too. “It’s more interesting because you’re fluctuating between the two and the time seems to go by faster,” she says. (If you don’t currently exercise, you may want to start with just 10 minutes, or talk to your doctor about the routine.)

Heisz is currently looking into the benefits of low-intensity exercise on memory; early findings suggest it can have a similar effect — you just have to do more of it. Instead of 20 minutes of intense spin class, 30 minutes of gentler cycling or light jogging seems to do the trick.