THE BRAZEN CAREERIST- Caffeine nap: Try new energy booster

I've been doing a little research on sleep, and I've found that the more I understand about nutrition, the better I eat. I thought the same would hold true for sleep. In fact, though, on my way to convincing myself to sleep more, I found mostly research to help me sleep less.

But first, here's the research that will make you want to sleep: If you don't sleep, you're more likely to be obese and dumb, both of which are bad for your career.

People who get fewer than six hours of sleep function like drunk people at work. For example people who missed just one night of sleep scored 20 percent lower on math tests than they did when they had eight hours of sleep. And, people who get significantly fewer than eight hours of sleep a night are more likely to be obese, according to a study at the University of British Columbia.

Here's some research I didn't expect to see:

Humans need only six or seven hours of sleep. In fact, if you get more than that, you're likely to die earlier, according to researchers from the University of California at San Diego.

And here's more good news for the chronic night-owl who suffers with a day job: If you miss out on sleep, you don't need to make it all up. Only about a third of this lost sleep needs to be regained. The people who spend all weekend in bed catching up don't need that much sleep. They just like lying around in bed.

You don't even have to wait for the weekend to make up the sleeping time: power naps are in fashion­ at least among elite athletes and soldiers in Iraq, both of whom are required to take power naps before a major effort. The power nap should be exactly 20 minutes, according to sleep researcher Sara Mednick, at the Salk Institute for Biological Studies. Your sleep cycles run in 90 or 120 minute cycles, but after 20 minutes you've done the most important part of your sleeping.

I'm an easy convert to the idea of a power nap, but I never seem to wake up at that magical 20-minute mark when researchers say that I won't be groggy. I am, in fact, routinely groggy after my supposed power nap. And that groggy feeling when you wake up is the equivalent of you after four beers, according to Kenneth Wright at the University of Colorado. So the power nap is not for me.

But here's my favorite study, the one that really pulls everything together: the caffeine nap. This is a nap that allows me to compensate for not quite getting my seven hours of sleep a night, but I don't feel groggy after the nap.

Researchers at Loughborough University in England found that coffee can clear your body of the sleep-inducing chemical adenosine. The best way to handle the caffeine is to chug a cup of coffee and then immediately take a nap, before the caffeine kicks in and makes for jittery napping. The nap should last exactly 15 minutes, which is the point at which the caffeine starts to gain traction in your brain.

I did it today, head on the table, next to the computer, when I was sure that I could not keep my eyes open another second: 15 minutes, and boom! I was writing again with perk and verve.

Of course the caffeine nap will save the world from having to sleep. For one thing, there's no research to show that caffeine nap can help you beat the correlation between lack of sleep and obesity. But I'll tell you, I'll never aim for eight hours of sleep again.