Lift Weights to Improve Your Memory

Exercising with weights for as little as 20 minutes a day may improve your memory by up to 10 percent, according to researchers at Atlanta’s Georgia Institute of Technology.

Researchers devised a study to test a suspected link between non-aerobic physical exertion with weights and memory. The study included 46 people between the ages of 18 and 30, who were divided into an active and a control group.

First, both groups were shown a series of photographs. "Everyone in the study looked at a series of 90 photos on a computer screen," explains lead researcher and graduate student Lisa Weinberg. "Some of the images were positive, such as children playing on a waterslide; some were negative like mutilated bodies and a poisonous snake and some were neutral, like a clock."

Next came the workout. On a calibrated machine designed to monitor participants’ consistency of effort, members of the active group extended and contracted each leg 50 times; this took an average of 20 minutes. The other group sat on the equipment and allowed the machine and the experimenter to do the manipulations. During the workout, blood pressure and heart rate was monitored and each participant also contributed saliva samples. (Physical activity releases hormones that affect certain brain activities, which can be measured in the saliva.)

When participants returned to the lab 48 hours later, they were shown 180 pictures—the 90 originals along with 90 new photos randomly added to the mix. "The group who exercised recalled 10 percent more than the group who did not, suggesting that resistance exercise [which involves exercising muscles against external resistance, often in the form of weights] makes a difference," Weinberg says. (No one, however, recalled 100% of the photographs.)

How Memory Works

Memory making occurs in three phases: encoding or learning, consolidation (absorbing and storing the information), and retrieval (recalling the experience).

There’s one other important part of the memory-making process: sleep. "It aids the consolidation phase," says Weinberg, explaining why the study participants weren’t tested on the recall of the photographs immediately following the workout. "We believe exercise plays a role in improving the consolidation phase so that retrieval is more successful."

More About the Study

The study is unusual in several ways: First of all, "Other memory studies have used aerobic forms of exercise, but we wanted an exercise accessible to more people," Weinberg says, since "Many people are not able to take part in prolonged, aerobic activity like a three-mile run, for instance." But with resistance exercises, "Someone who has a disability or limited flexibility elsewhere in the body can still reap benefits." Weinberg notes that while the exercise investigated in this study targeted the legs, arm resistance exercises would likely be just as effective. Studying exercise's effect on memory in younger people was also a departure: "The relationship between exercise and memory has been studied before, but most of those studies looked at older people exercising aerobically for weeks or months," Weinberg notes. But Weinberg adds a word of warning: While 20 minutes of exercise resulted in better memory for the study participants, this is well below the exercise levels leading health experts recommend: “The American Heart Association, the CDC [Centers for Disease Control and Prevention] and others suggest exercising 150 minutes per week at a moderate level for optimal health," she says. Nonetheless, “There are definitely exercise-induced memory benefits without committing to a long workout.”

Do Try This at Home

Although an exercise machine was used in the experiment, Weinberg says the workout can be reproduced at home. If you’ve been given the go-ahead to exercise by your physician, "Performing squats repetitively using weights would simulate what we did in the lab," the grad student says. "Other types of resistance exercises, like push-ups, would also be beneficial to memory."

So, the next time you need to remember something important, try working out with weights a few days before. It just might make your next test, presentation or job interview more memorable!

Lisa Weinberg approved this article.

Sources

Phone interview with Lisa Weinberg, 19 December 2014.

Georgia Institute of Technology. "Lift Weights, Improve Your Memory: Study Finds That one Short Bout of Resistance Exercise Can Enhance Episodic Memory." GT News. Posted 30 September 2014.

University of California, San Francisco. "Episodic Memory." UCSF Memory and Aging Center. Brain 101. Topics in Neuroscience. Updated 8 December 2014.

"Recommendations for Physical Activity in Adults." The American Heart Association. Updated February 2014.

"Resistance Training for Health and Fitness." American College of Sports Medicine. Accessed January 14, 2015.