A nap or a quick workout... How do you enhance your memory after lack of sleep?

Sleep deprivation makes it more difficult to concentrate and receive new information. For people who work nights or sometimes experience periods of severe sleep loss, getting adequate rest may not be possible at the same time.

Is there another way to help the brain focus besides sleep? A recent study published in the scientific journal "Proceedings of the National Academy of Sciences" compared two strategies for protecting memory after sleep deprivation: doing aerobic exercise and taking a nap.

The researchers wanted to know if a short period of exercise could provide some of the cognitive benefits that a nap provides. The results suggest that this may be possible.

To understand the importance of these results, the following questions are answered by Ofoq News' health expert, Dr. Leana Wen, an emergency physician and associate clinical professor at George Washington University in the United States. Ofoq News: How did researchers determine the effect of exercising compared to taking a nap?

Dr. Leana Wen: The study included 54 healthy adults between the ages of 18 and 35 years. The participants stayed awake for 30 straight hours and were then randomly divided into three groups.

The first group rode a stationary bike for 20 minutes at a moderate to high intensity, equivalent to approximately 80% of their maximum heart rate. The second group got a chance to sleep for 90 minutes, while the third group, the comparison group, sat on a stationary bike for 20 minutes without exercising.

The participants were then shown 150 images, while the researchers recorded their brain activity using electroencephalography. Participants did not know that a memory test would be administered later.

Three days later, after they had had a chance to recover from sleep deprivation, they were shown the original images mixed with new images and asked to identify which ones they remembered. People who exercised were able to correctly identify 56% of the images, compared to 57% among those who took a nap, and only 46% among the group that did not exercise or take a nap.

The results of the exercise and nap groups were clearly better than the third group, and no significant difference appeared between the effect of exercise and the effect of nap on memory. However, people who took a nap felt less tired after sleeping, while those who exercised still felt tired at a level similar to the non-exercise group.

However, their performance on the memory test was much better. Ofoq News: How can 20 minutes of exercise help memory after a person has been awake for a long time?

Dr. Leana Wen: Sleep deprivation disrupts the brain's ability to record new information. The longer the period of being awake, the more the body needs sleep, and the less efficient the neural processes needed to form memories become.

Recordings of brain activity indicate that exercise helped counter some of these effects, as it reduced one of the signs of nervous fatigue in the areas of the brain responsible for memory. Exercise potentially helps a sleep-deprived brain use its remaining cognitive abilities more efficiently.

Short bursts of activity fall under a concept known as “exercise bouts,” that is, brief periods of movement that may last from 30 seconds to several minutes, such as stair climbing, brisk walking, squats and other activities that raise the heart rate. Previous studies have shown that these short activities may improve cardiorespiratory fitness, and may contribute to reducing the risks of cancer and dementia.

Horizon News: Did exercise and taking naps help the brain in the same way? Dr. Leana Wen: Not quite, and in my opinion, this was one of the most interesting findings.

Exercising and taking a nap led to similar benefits in memory performance, but through different neural processes. Naps reduce fatigue and the brain's biological need for sleep, i.e. give the brain some of the sleep it needs.

Exercise does not reduce the body's need for sleep, but it may make information processing and memory more efficient despite continued sleep deprivation. Ofoq News: Can someone who suffers from sleep deprivation exercise instead of taking a nap?

Dr. Leana Wen: No, exercise cannot replace sleep. Sleep is essential for regulating the immune system, metabolism, and many brain and body functions.

A 20-minute exercise cannot perform these functions, although regular exercise actually helps with sleep, and vice versa. The study asked a more specific question: If a person has already suffered from severe sleep deprivation, can an intervention protect a specific cognitive ability, namely the formation of new memories?

Regarding this finding, under the specific conditions of this study, exercising for 20 minutes and taking a nap for 90 minutes led to similar results. The study results also do not mean that exercising makes driving or performing dangerous tasks safe when feeling extremely tired.

Ofoq News: Can we apply these findings to people who feel tired due to a bad night's sleep, or those who regularly do not get enough sleep? Dr. Leana Wen: The study has important limitations, as it included a small number of healthy young people who remained awake for 30 hours in laboratory conditions.

We don't know if the same results apply to older people, sick people, or people with chronic sleep deprivation. The study also did not prove that exercise restores attention, response speed, and the ability to make decisions to normal levels.

Ofoq News: What should people do if they are sleep deprived but need to perform their tasks efficiently that day? Dr. Leana Wen: The priority should always be sleep, and adults should regularly get at least 7 hours a day.

If adequate sleep is not possible, a nap may help. If a nap is not possible, a short period of aerobic exercise, such as brisk walking, climbing stairs, or riding a bike, may be useful before doing work that requires learning and memory.

Caffeine can also temporarily increase alertness and concentration, but it does not reverse the effects of sleep deprivation. It is also important to eat balanced meals, drink enough water, and avoid heavy meals and alcohol consumption.

It must be realized that these methods only mitigate some of the effects, and do not make risky activities safe when severely sleep deprived.