A restless night doesn’t just make for an irritable day at the office. It can eat away at our recall, making it harder to retain information and learn new skills.
It’s well known that physical activity offsets a loss of sleep by releasing endorphins that reduce anxiety, realigning circadian rhythms, and triggering a cooldown that initiates the sleep cycle.
Given that exercise can help us catch some zees, researchers from Concordia University in Canada tested whether it also protects our memory from the corrosive effects of sleep loss.
A group of 88 healthy young volunteers was randomly divided into one of four groups. Half received a typical amount of sleep; the other half was permitted a mere 4.5 hours of the recommended 8.5 hours of nightly slumber. Each group was then divided again, with half of each group either engaging in half an hour of moderate-intensity cycling or simply sitting in a chair and doing nothing for 40 minutes.
Before hitting the sack, each group participated in an image-matching game, determining whether faces in a sequence were part of a set they’d been shown previously or were new to that evening’s session. A similar test was then repeated the following day.
As might be expected, nothing beats a good night’s rest. Those who slept soundly aced the memory game the following day. Those who didn’t get enough sleep were significantly slower in their answers.
Yet doing a spot of exercise seemed to help. Their recall was far less delayed than the recall of those who rested before bed.
The study adds vital evidence in support of moderate physical activity’s impact on the functioning of a sleep-deprived brain, though the researchers acknowledge their method has a few limitations. Extending the study to test the same participants under different conditions would help remove confounding variables (not that a lot of volunteers would be expected to stick with such a long experiment).
Deep sleep – the kind we get when our brain slips into a slow-wave state of function – is vital for memory retention. It also happens to be the kind of sleep we miss out on when we stay up to cram for an exam, finish those work emails, or binge one more episode of the latest Netflix true crime documentary.
It’s not just our memory that suffers, either. Poor sleep can elevate inflammation, interfere with our metabolism, and put us at risk of chronic health conditions such as heart disease and dementia.
Swapping out a bit of late-night doomscrolling for some early-evening park strolling is a cheap, simple, non-pharmaceutical antidote to fuzzy brains and an early grave.
This research was published in the journal Sleep.
Source: Phys.org
