There is nothing wrong with down time. Funny that this is something that I struggle with, with so many goals and so little time.  It is unhealthy to run 110 miles per hour everyday 7 days a week. Something has to give, someone is going to cry "Uncle".  So remember to take care of yourself, take some time to be down and recharge. Vacations, days off just to get away.  If not over time you will find that your productivity may drop and you may become less effective.