When you get older and you have implants in your bottom what kind of garment will keep implants from going down?

Hello I'm sixty-four. I had implants in my bottom for a while but since I've gotten older things you know your body changes. I'm trying to find out what kind of garment I can wear to keep my implants from going down like my skin... they have weight to them so that way they don't go lower I feel uncomfortable as I age. Thank you very much I don't know who to ask. Thank you. They were put underneath the muscle but as you age so does everything else!