Working hard and smart is great but taking some time to rest and rejuvenate your body, is very important to be effective in your career, purpose, business or assignment.
Mark 6:30-32
The apostles gathered around Jesus and reported to him all they had done and taught. Then, because so many people were coming and going that they did not even have a chance to eat, he said to them, “Come with me by yourselves to a quiet place and get some rest . “So they went away by themselves in a boat to a solitary place
From the above context, we realize Jesus personally advised His disciples, to follow Him to a quiet place, where they would have some rest, away from the crowd. He knew very well, if His disciples did not have enough rest to rejuvenate from their previous missionary work, they would not have enough energy for the next assignment, which was awaiting them .He personally lived by example and taught His disciples the importance of rest.
Take some time off and rest.