Exercising Four Hours After Learning a New Material Could Improve Memory, Study Shows

A new study suggests that exercising can not only improve physical health but also boost memory consolidation if done in a specific time after learning a new material.

The study, published in the Cell Press journal Current Biology, is conducted to determine the effects of one session of exercise after learning on memory consolidation and long-term memory.

For the study, researchers enrolled 73 healthy volunteers. Each participant was asked to learn 90 picture-location associations over a period of approximately 40 minutes. The researchers then divided the participants into three groups.

The first group performed one session of physical exercise immediately after the learning process. The second group was asked to exercise four hours after. On the other hand, the third group did not perform any exercise at all.

The participants who were asked to exercise performed 35 minutes of interval training on an exercise bike at an intensity of up to 80 percent of participants' maximum heart rates.

Two days later, the participants were given a test to determine how much they remembered in the picture-location associations, while the researchers are imaging their brains using magnetic resonance imaging (MRI).

Surprisingly, the researchers discovered that participants in the group who were asked to exercise four hours after they learned the new material has retained the information better 48 hours later, compared to those who performed exercise immediately and those who did not have exercise at all. MRI imaging also revealed that those who performed a delayed exercise have more precise representation in their hippocampus when they answered the question correctly.

"It shows that we can improve memory consolidation by doing sports after learning," said Guillén Fernández of the Donders Institute at the Radboud University Medical Center in the Netherlands, in a statement. "Our results suggest that appropriately timed physical exercise can improve long-term memory and highlight the potential of exercise as an intervention in educational and clinical settings."

However, it is still not clear how or why delayed exercise improve memory consolidation. Early animal studies suggest that catecholamines, a naturally occurring compound in the body including dopamine and norepinephrine, can improve memory consolidation. And one way of boosting catecholamines is through physical exercise.