Whether you are cramming for an exam or simply want to give your memory a boost, doing some physical exercise straight after a learning session may be of great help - if you are a woman, that is.
A new study published in the journal Cognitive Research: Principles and Implications shows that just 5 minutes of light physical exercise following a learning session improves memory in young women. The study's first author is Dr. Steven Most, of the School of Psychology at the University of New South Wales in Sydney, Australia. He and his team conducted four experiments that included a total of 256 participants.
In the first experiment, 74 undergraduate students - 38 women and 36 men - aged 19.9 years, on average, were divided into two groups. One group engaged in 5 minutes of low-impact cardio exercise (such as step exercise) before a learning phase that involved remembering name-face pairs, while the other group engaged in another, non-exercise activity. After 24 hours, the researchers tested the participants' memory of their previous learning phase. The same conditions were repeated but with 5 minutes of activity after the learning phase.
In the second experiment, Dr. Most and team wanted to see if the "post-learning" exercise benefits noticed in the first experiment would be replicated if they eliminated sleep as a possible consolidation phase. The memory test was therefore administered on the same day as the learning phase. The researchers also altered the non-exercise activity.
In the third experiment, the researchers replaced the face-name association task with one that involved abstract shapes. The reason for this was that some studies have previously suggested that emotional material such as face stimuli may be more easily remembered than neutral material.
Exercise boosts memory retroactively
By this point, the researchers noticed that women who engaged in mild physical activity after learning performed considerably better in memory tests than the women who did not exercise.
"The effect came into play only after participants had studied the material, meaning that it retroactively boosted learning of the material," says Dr. Most.
In fact, the effect was at its strongest in the first experiment. For this reason, the researchers tried to replicate the first experiment in a fourth one, wherein the conditions remained largely the same but the non-exercise activity differed.
The fourth experiment further validated the beneficial memorial effects of exercising after learning. "But mysteriously," says Dr. Most, "this effect did not emerge among men in any of the experiments."
"It's unclear whether this is a true sex difference or whether there was something about the experiment's conditions that allowed the effect to emerge among women and not men." A potential bias in the study, Dr. Most says, might have been the fact that in the three of the four experiments that involved facial recognition and name-face association, the faces were all male. Dr. Most thinks that it is possible that females reacted better to male faces and that conversely, men would have remembered the names better if they had been exposed to female faces. The study's first author comments on the significance of the findings.
"Some schools are under pressure to cut back on recess in order to increase time in the classroom, but it may be that encouraging physical activity breaks at several points during the day can actually help with the retention of classroom learning."
- Dr. Steven Most
But "more research needs to be conducted to conclude that with certainty," he cautions. "There is also scope for further study to understand how much exercise is optimal, how long before or after learning is most effective, and who benefits most."