How to keep an active brain, especially in old age, has always been the concern of many of us who led a busy life throughout most of our working days. Cryptic crosswords and fiendish puzzles are known to keep the mind sharp but scientists have now found a far less testing way of exercising the brain.
An hour’s siesta can prevent your brain from ageing by five years when it comes to memory and thinking. According to the study, a 60 minute sleep was the optimum amount of time, with a shorter or longer period not producing the same results.
Scientists analysed 3,000 Chinese people over the age of 65, 60% of whom said that they had a siesta after lunch ranging between 30 and 90 minutes with an average of 63 minutes. They were asked a series of simple questions about dates and seasons. After submitting their responses, the pensioners were given a basic maths problem and asked to memorise words and copy single geometric figures.
The study, which was carried out by the Health in Aging Foundation and published in the Journal of the American Geriatric Society, concluded that people who took an hour long nap after lunch performed better in mental tests than the people who did not nap. Those who slept for about an hour also did better than people who took shorter or longer rests. People who took no naps, short naps or longer naps experienced decreases in their mental ability that were between four and six times greater than people who took hour-long naps.
Junxin Li, lead author of the study, said: ‘These people also experienced about the same decline in their mental abilities that a five-year increase in age would be expected to cause.
‘Cognitive functions were significantly associated with napping. Between groups, comparisons showed that moderate nappers had better overall cognition than non-nappers or extended nappers.
‘Non-nappers also had significantly poorer cognition than short nappers.’
‘In multiple-regression analysis, moderate napping was significantly associated with better cognition than non- and extended napping after controlling four demographic characteristics: body mass index, depression, instrumental activities of daily living and social activities, and night-time sleep duration.’
Dr Li added, ‘A cross-sectional association was found between moderate post-lunch napping and better cognition in Chinese older adults. Longitudinal studies with objective napping measures are needed to further test this hypothesis.’
David Reynolds, chief scientific officer at Alzheimer’s Research UK, said: ‘This study adds to the growing evidence that sleep has a beneficial impact on learning and memory and it’s positive to see that this holds true in a study of older adults. Sleep disturbances are common in Alzheimer’s and while these are studies investigating the role of sleep in the disease, the study has not looked at whether afternoon naps may protect against Alzheimer’s or other dementias. It’s important for future research to delve deeper into the science behind sleep and cognition to shed light on those sleep patterns that may hold the most benefits for our brain health as we age.’
Last year scientists found that a long afternoon nap could help boost the brain power of men and that women benefited from longer nightsleep. Researchers from the Max Planck Institute in Munich believe that the differences between how sleep affects the sexes could be because of the way men’s and women’s brains are structured as well as how hormonal changes affect the body during the day.
Well, I believe that as you grow older you still need an eight hour sleep if possible, especially if during the day your work entails a lot of brain activities which can be gruellingly tiring. As for an afternoon siesta, I wish I had the time to enjoy its beneficial impact. I will nevertheless try to snatch a nap or two over the weekend and perhaps then I will become addicted to its immeasurable health windfall.