Resistance Exercise Helps Boost Episodic Memory

Study finds that intense workout helps boost long term memory.

Researchers at the Georgia Institute of Technology provide an interesting reason for people to hit the gym. According to the study, indulging in an intense workout i.e. a minimum of 20 minutes, helps enhance episodic memory also called as long term memory by 10 percent in healthy young adults.

Studies conducted earlier have also highlighted the association between exercise and improvement in memory. They mostly looked at aerobic exercise like running. But the current study shows how lifting weights helps improve memory.

In this study, the participants had to lift weights just once two days before the test. The researchers also had the participants study events prior to the exercise but  not after workout.  Previous animal research suggests that the period for learning is when the stress triggered by exercise most likely benefits memory.

"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.

To begin with, the participants were made to view a series of 90 photos on a computer screen. The images were evenly divided between positive, negative and neutral pictures. The subjects were also asked to try and remember the pictures. After which, they were made to sit on a leg extension resistance exercise machine.

Half of the participants extended and contracted each leg at the personal maximum effort nearly 50 times. On the other hand the control group just sat in the chair and allowed the machine and the experimenter to mover their legs. During this, process, the researchers monitored the participants' blood pressure and heart rate. The participants also provided samples of their saliva that were further used to measure the levels of neurotransmitter markers associated with stress.

After 48 hours, the participants returned to the lab and again viewed a series of 180 pictures in which 90 original were mixed with 90 new pictures. It was observed that the control group successfully recalled 50 percent of the photos from the first session. Those who exercised remembered 60 percent of the photos.

Although weight exercises were used, the researchers noted that resistance exercise like squats or knee bends gave the same result. They noticed that people are more likely to remember emotional experiences after acute stress.

"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."

The finding was documented in the journal Acta Psychologica.