New Study Shows Weight Training Enhances Memory

Rebecca Lewis October 03, 2014

It is a common idea that exercise is good for the brain, just as it is good for all other parts of the body. But a new study went deeper into the brain-boosting benefits of physical activity, and found that an intense workout of as little as 20 minutes can enhance episodic memory.

While many existing studies have drawn a link between aerobic activity (such as running) and memory, the new research looked at anaerobic activities such as lifting weights.

For the study, researchers had participants lift weights just once two days before testing them and also had participants study events just before the exercise rather than after workout. They did this because of extensive animal research suggesting that the period after learning (or consolidation) is when the arousal or stress caused by exercise is most likely to benefit memory.

In the experiment, participants looked at a series of 90 photos on a computer screen. The images were evenly split between positive (i.e. kids on a waterslide), negative (mutilated bodies), and neutral (clocks) pictures. They weren’t asked to try and remember the photos. Everyone then sat at a leg extension resistance exercise machine.

Half of them extended and contracted each leg at their personal maximum effort 50 times.

The control group simply sat in the chair and allowed the machine and the experimenter to move their legs.

Throughout the process, each participant’s blood pressure and heart rate were monitored. Every person also contributed saliva samples so the team could detect levels of neurotransmitter markers linked to stress.

Then, the participants returned to the lab 48 hours later and saw a series of 180 pictures — the 90 originals were mixed in with 90 new photos.

The control group recalled about 50 per cent of the photos from the first session. Those who exercised remembered about 60 per cent.

“Our study indicates that people don’t have to dedicate large amounts of time to give their brain a boost,” said Lisa Weinberg, the Georgia Tech graduate student who led the project.

Although the study used weight exercises, Weinberg notes that resistance activities such as squats or knee bends would likely produce the same results.

While all participants remembered the positive and negative images better than the neutral images, this pattern was greatest in the exercise participants, who showed the highest physiological responses.

The team expected that result, as existing research on memory indicates that people are more likely to remember emotional experiences especially after acute (short-term) stress.

Researchers say that although a definitive physiological explanation of the results remain cloudy, existing human research has linked memory enhancements to acute stress responses, usually from psychological stressors such as public speaking.

“Even without doing expensive fMRI scans, our results give us an idea of what areas of the brain might be supporting these exercise-induced memory benefits,” said Audrey Duarte, an associate professor in the School of Psychology. “The findings are encouraging because they are consistent with rodent literature that pinpoints exactly the parts of the brain that play a role in stress-induced memory benefits caused by exercise.”

Source of this article: Weight Training Can Enhance Memory