[randlet]

This advice is repeated a lot, but motivation is fleeting and you just have to make it part of your routine in the same way that brushing your teeth, showering, paying your bills, cleaning your house, and so on are.

If it helps, you can think of it like "going to work". Very few people are lucky enough to feel any sort of intrinsic motivation to show up at work every day, but they do so because of the consequences are disastrous if they don't. The analogy isn't perfect since the long term consequences of ignoring your health are farther in the future, but the upside is that after exercise you get shorter term feedback in improved mood, sleep, concentration etc. You just need to show up and do the work.

[atemerev]

"Having a routine" is exactly what doesn't work with ADHD. We can't do routine. Anything but this. Some of us are struggling with brushing teeth every day, or showing up at work. Even though when hyperfocused, we can do a week's work in a day, or successfully prepare for a difficult exam in a night, but doing something regularly — that's something we absolutely don't have.

[randlet]

If you're struggling with brushing your teeth,showing up to work or other basic self care, then I don't think the discipline to exercise will manifest itself and it is likely time to speak with a professional.

[atemerev]

I do have a therapist who is an ADHD specialist, but it doesn’t help much. “Well yes, your case is quite severe, try to do what you can and see how it goes”. I’m trying.

[AlanYx]

One technique that I've found helpful is setting up triggers, rather than routines. A trigger being a commitment of the form, in circumstance X, I will do Y. e.g., When I enter the bathroom the first thing in the morning, I will do some pushups. At a high level, it accomplishes the same thing as a routine, but it doesn't require the global discipline of a routine. With triggers you're only responding to the moment.

[npwr]

That is a very neat idea. It might just work for me. Thank you

[erybodyknows]

This is the answer. Use any fleeting motivation to construct the habit. Do not rely on “feeling like it”. Once you’ve created the habit, it will feel uncomfortable not exercising.

[obloid]

I, and I suspect other ADHD people, don't form those habits. I've for years read things like "you don't have to remind yourself to brush your teeth because it's a habit. You can make exercising a habit, too."

But for some of us, we do have to remind ourselves to brush our teeth, or eat, or whatever thing the average person does "automatically".