Sudoku? Try a nap after gym to boost your memory

Forget about sudoku, cryptic crosswords or brain-training exercises.

Researchers claim that one of the best ways to bolster your memory is to have a quick nap after exercise.

A study by scientists in Canada has found healthy young adults who dozed for an hour after a gruelling workout scored much better on memory tests.

Scientists have known for years that both regular, adequate sleep and frequent bouts of physical activity can, on their own, enhance memory. 

But the latest findings, by researchers from Concordia University in Montreal, show the best results come from combining the two.

The team recruited 115 young men and women in their early to mid-twenties.

The volunteers were split into three groups. One was told to do 40 minutes of moderate intensity cycling on an exercise bike. A second group was told to snooze for an hour. And the third group did both.

All the volunteers then completed a task where they had to try to memorise 45 types of pictures which they were later asked to recall. 

The results, published in the journal Sleep, showed the exercise and sleep group were able to accurately recall around 84 per cent of the images. But those who just napped could remember only 81 per cent and volunteers who just exercised only 78 per cent.

Sleep is known to consolidate memories by strengthening connections between brain cells and transferring information from one brain area to another. 

Exercise, meanwhile, works by boosting production of growth factors – chemicals that control the survival and health of new brain cells.

The researchers said exercise and sleep seem to operate ‘synergistically’, adding: ‘Participants who experienced both exercise plus nap were significantly more accurate than those who only napped and those who only exercised.

‘Our results demonstrate short-term exercise and a nap improve recognition memory over a nap or exercise alone.’

Independent sleep expert Dr Neil Stanley said combining the two may boost memory because exercise is more likely to trigger deep sleep – the phase where memories are properly stored away. 

He said: ‘By exercising first, you are improving the quality of the nap and promoting the kind of sleep associated with memory.’