to become unrestrained and go to excess; to lose all restraint; to lose one's tension and become relaxed; to let go; to become disorderly; to be scattered
the bounds of reason; the limits of (common) sense
to cut loose; to act without restraint; to throw off all inhibitions; to go wild
to weaken (of willpower, solidarity, etc.); to lose one's edge; to become less tense; to become lax (of discipline, rules, etc.)
to pull oneself together; to get one's act together; to brace oneself
to hoop; to put a hoop on; to bind a barrel with hoops