I have to nap whenever I feel a slump coming on. I don't sleep well at night at all, never have, never will (per my doctor). Luckily, I don't work now so I CAN nap or sleep when it comes on. I take a late afternoon nap most every day unless I have plans. I have been unable to push thru the slump. Sometimes, I'm awake at 4:00 in the morning and sometimes I might sleep until 9:00...just never know!! But I have Fibro and Chronic Fatique Syndrome so that's part of my problem.