Study suggests that people nap for 25 minutes or less, or sleep for a full cycle of 90 minutes, in order to avoid 'sleep inertia.'

Study suggests that people nap for 25 minutes or less, or sleep for a full cycle of 90 minutes, in order to avoid 'sleep inertia.': https://ift.tt/2Owk9ju Read more... https://ift.tt/2PecIgh