I'm comfortable in my own skin, it's my clothing that's the problem
Fitness. Ah yes, I remember that. Back in the day when I kayaked, ran, worked out at the gym, biked, and went for long hikes - all in the same week. Every week. Now I'm ten pounds heavier and feeling like a sausage.
My problem is that I'm content. I don't feel like a lioness in a cage any more, so I'm not driven to exercise. Even though I know how important it is, especially for those of us with ADHD, it's everything I can do to get in half an hour a week. I'm just not motivated like I used to be.
So I hired a personal trainer. He works for a dollar a week. What, you say? A dollar a WEEK?!
Yes, that's right. He's my son. He created a workout plan for me. And wrote up a contract - I'm free to discontinue his services after two months. He counts my crunches as I do them, and runs with me. He's very motivated by money, but more than that, I think he digs telling me what to do. I let him be the boss. I encourage him to yell at me when I'm being lazy. I even agreed to let him shoot me with an airsoft gun if I become difficult, but so far, it hasn't come to that. We're both having fun. And we're both exercising. Every day.
If you have a child, or access to one, I highly recommend this approach. You may have to fork over more than a buck (sssh, don't tell my son), but it will be worth it.