I've never been a person to take naps, then again sleeping at night has always been a challenge for me too – at least until I learned to meditate regularly which has improved overall stress levels and paved the way for much better sleep in general.
Lately though I have been taking more afternoon naps on the weekend and had always wondered why some naps left me feeling refreshed and alert while others left me feeling worse than before.
Digging into the considerable research helped me understand the optimal nap patterns depending on what you are trying to achieve:
Source: Wall Street Journal – http://www.wsj.com/news/articles/SB10001424127887323932604579050990895301888
For me the lesson was clear, if you are going to nap try to avoid the 30-minute nap – either go for the short "cat nap" or try to give yourself 60-90 minutes and you'll wake up much more refreshed.
Interestingly, I have found just this pattern works when I travel overseas where I arrive in Europe in the morning (I can't sleep well on a plane) – get into my hotel as early as possible, draw the shades and get a 90-minute nap in is the perfect way to acclimate to the new timezone.
What about you, do you take naps and have you noticed a difference in how you feel depending on how long your nap is?