If you needed one more reason to hit the gym, here is one you didn’t expect: studies have revealed that short episodes of high intensity training can improve episodic memory (the memory of autobiographical events).
The study was conducted by researchers at Georgia Institute of Technology, who concluded that high intensity training, even for just 20 minutes, can improve memory by up to 10% in young, healthy individuals.
Episodic memory is the memory where events from the past get stored or, if you will, a collection of personal experiences.
What is even more interesting is that, if many previous studies have suggested that aerobic training, such as running, can help memory, this particular study was conducted on subjects performing weight lifting.
At the beginning of the study, the subjects were shown 90 photos on a computer. The images were split into positive (such as, for example, children playing), negative (such as, for instance, mutilated bodies) and neutral (a clock). The participants were not asked to memorize any photo, but each of them stayed, at all time, on a leg extension fitness machine. Half of them strained their muscles on each leg at a maximum level of effort 50 times each, while the participants in the control group just stayed on the machine, while another person was moving their legs. During the test, each participant has their blood pressure and heart rate measured and saliva samples were collected in order to measure the level of neurotransmitters that indicate the level of stress.
The participants came back to the lab 48 hours later and view again a series of 180 photos, among which there were 90 of the initial photos. Those in the control group remembered and identified approximately 50% of the photos from the first session, while the others remembered approximately 60% of them.
Previous studies made on animals have shown that after the learning stage, excitement or stress caused by physical effort is beneficial for memory. In this particular study, although all participants remembered the positive and negative images better than the neutral ones, this was made more obvious in the case of participants who have exercised during viewing and who had the strongest psychological response.
Why does it work? Well, some research has connected memory stimulation with stress, while other studies have identified a hormonal response of the body that helps access memories. Either way, scientists agree that you don’t have to be fit to get this results. You just have to be determined enough to do your exercise.