In other words, let's have a day off. The man Christ Jesus determined that he and they needed that. Sloth is a sin but relaxation is not. Creative resting is the great entertainment. God made us with bodies and no other justification is needed for taking part in physical activities than that.
Games are a part of learning.
In sports we learn such things as other children must have their turn, pity for the weak, admiration for the gifted, generosity for skill displayed and fair play. If these attitudes are not possible in sport so that all that matters is winning then those games are off-limits for the Christian. Our dexterity, suppleness and strength we give to God as our offering, and we ask him to help us use them in a manner that pleases him. Jesus grew in stature and that is our calling too. It is still true.