Two studies are at odds over whether napping helps or hurts cardiac health. Whether or not napping reduces the risk of heart attack, during the past decade some employers have started promoting napping at the office.

Harvard University gave workers the excuse they were looking for last week when they said a nap after lunch reduce the risk of heart attack.

But time-conscious managers may have a rebuttal: though much forgotten in the press, another Harvard study, published several years earlier, made its own news splash by arguing that naps are associated with a higher incidence of heart attack.

So, who to believe?

I personally feel that there are times during the day, especially around 3-4 pm, when a power nap of 10-15 minutes really leaves you feeling refreshed and energised.