A 45-minute catnap helps lower blood pressure, American researchers reported last week. They said a daytime snooze could improve heart health, particularly if youre not getting as much sleep as you should at night. This follows a recent six-year Greek study which found that people who took a 30-minute siesta at least three times a week appeared to have a 37 per cent lower risk of heart-related death. The theory is that napping, by encouraging you to relax, reduces blood pressure. It can also help your brain. A study by the University of California found that after a 90-minute daytime sleep, volunteers performed better in complicated written tests than those who were kept awake. The study leader, Dr Matthew Walker, says napping works over and beyond helping you catch up on lost sleep: 'At a neuro-cognitive level, it moves you beyond where you were before you took a nap. This has been backed up by research on pilots which shows that a 26-minute in-flight nap (during which the plane is manned by a co-pilot) enhances performance by 34 per cent and overall alertness by 54 per cent. The researchers suggest the brain uses this snatched extra sleep to help it process short-term memories (effectively moving them into a longer-term storage area in the brain), creating 'space for new facts to be learned. But its not just enough to put your head down. Here, we show you the right way tonap. THE BEST TIME TO SLEEP Nap too early in the day and you may find it difficult to fall asleep; too late and it may affect your ability to fall asleep that night. Our energy levels normally dip between 1pm and 3pm. This is because we get a natural rise in the hormone melatonin (the sleep hormone, levels of which normally peak at night), so this is a good time to nap. 'Larks (who go to bed early and are active early in the morning) should nap at around 1pm. Owls (who go to bed after midnight and sleep late in the morning) should nap at around 2.30pm. TRICKS TO HELP YOU SNOOZE * Choose a dark room or wear an eye mask, and lie down (it can take 50 per cent longer to fall asleep while sitting). * To maximise the benefits, drink coffee before your nap - caffeine takes 20 to 30 minutes to take effect, so will kick in just as youre waking. * If sleeping eludes you, close your eyes and concentrate on your breathing. Dr Ramlakhan recommends breathing deeply and slowly. * Bizarre as it sounds she advises: 'Mentally whisper the word iiiiiin as you inhale and ooooout as you exhale. Daily Mail