been proven that 45mins to an hour is the optimal amount but as little as 20mins is still helpful if very tired.
more than 1hr 15 and you go into a deeper sleep and are likely to feel drowsy for a long time after you wake up.
tip: take a korean ginseng energy tablet right before your nap and it'll be kicking in as you wake up :)
"what so you not coming out tonight anymore?"
"yeh i'm fine all i need is a disco nap and i'll be back on form!"
Jane: I've gotta take a disco nap if we're going to make it to after hours.