I think I once read that Brady has it in his contract that he could work out with his personal trainer, at least when he was with the Patriots. They weren't in agreement with some of his workout stuff but there wasn't much they could do about it because of the contract. I don't know about his current contract but I remember that he violated some city ordinance working out on his own in the park last year during covid. I assume he probably still has it in his contract.