Nap

Research shows that a quick 40 winks can revitalise you – tests on pilots by the American space agency NASA found that a 26-minute nap boosted alertness by 54%. Just try to make sure you don’t sleep for more than 40 minutes – any longer and you’ll slip into deep REM sleep and will feel groggy rather than refreshed when you wake. Optimum snooze time is around 2-3pm – any later and you could interfere with your night-time sleep pattern – and try to doze in a quiet, dark, warm room.