Tired? Science Says Don’t Just Take a Nap or Drink Coffee… Do BothWhen you’re feeling tired, you may wonder if you should take a nap or drink coffee. But scientists have found that a “coffee nap”–meaning, drinking coffee followed immediately by a short nap–may be the best solution to beating fatigue. The reason? Effectively timing the interplay of caffeine molecules with adenosine receptors in the brain and sleep causes the caffeine to work better at keeping you alert once you wake up.

The research behind the “coffee nap” is mounting, and much of it looks very promising. A pairof studies found that people who took 15 minute coffee naps performed better in a driving simulator, while another study found that people who took a coffee nap performed better on memory tests than people who only took a nap or took a nap then used other methods of waking up. In that study, the coffee nappers also reported feeling less tired.

But the benefits of the coffee nap may not end there. For people who are chronically poor sleepers, coffee naps have been shown to help them perform better on cognitive tests despite being sleep-deprived overall.

It’s important that the nap be short: only 15-20 minutes max. It’s OK if you don’t fall asleep: just resting in a calm, tranquil, quiet environment has the same effects. But you have to drink the coffee relatively quickly, or it will mess up the timing of the reaction.