Try not to nap too close to bedtime or for more than 90 minutes.

CNN: Sleep tips for the road-weary

Exercise can help you sleep better at night, but not if you start too close to bedtime.

FORBES: 4 Ways To Sleep Better And Be Thinner

The National Sleep Foundation's 2013 Sleep in America poll, the task force of which was headed by Dr. Hirshkowitz, showed that exercise at any time of day, even close to bedtime, appears to be good for sleep.

WSJ: When It's Worth It to Skip a Workout and Sleep