Mark 6:31 And he said unto them, Come ye yourselves apart into a desert place, and rest a while: for there were many coming and going, and they had no leisure so much as to eat.
Jesus took His men and got away so that they could rest. Their rest would be short lived but He taught us that we all need a break.
As a missionary and pastor I have not been careful to take breaks. I believe that to be a mistake. I will say that before we take a break especially if we are in the ministry it should be that we are so busy that we really are working like is mentioned in the verse.
Without a doubt we should take time each week to spend concentrated time with our children and especially our spouse. We should take time to be alone with the Lord.
Time has a way of getting away from us. We end up like a cat chasing its own tail if we are not careful. Work at managing your time!