I'm not 30 yet but I'm pretty dang close and most of my friends are either right there with me or pushing 40 at this point. I hear pretty often about how lucky I am that I can eat however I want and don't have to work out and I'm still in great shape. I have a pretty obvious secret though. I mostly only eat healthy stuff that I cook at home, so when I go out I can eat the greasiest cheesesteak you can find it and not feel bad about it, and I do all my own home repairs and renovations. I don't go to the gym, but this morning I hauled 20 6x6x12 beams and about 40 bags of 80 cement to the back field by myself in the blistering sun to build a play structure for my kid. If I don't have anything to build I have a pallet of cinder blocks that don't current have a purpose that I just move around a big field back and forth to keep my hands calloused.
I'm pretty salty about it because I just started with a new doctor, and when asked if I work out I told him such, and he said that doesn't count and I should start going to the gym a few times a week to help my heart health. I think he was sponsored by planet fitness because he kept talking about it.