A man can overwork his dog by having it work 5 or 6 days in a row without any significant rest period. Overworking a dog is corrected by rest. It's not corrected by allowing a dog to recover while working. Your dog isn't going to be allowed a chance to recover while in a show as his opponent isn't going to allow that to happen. The animal has plenty of time to recover once the work is over for the day.
You're on of them players who turns "fatigue" off on pro evolution soccer.