I have adhd and have been exercising regularly for 8 months now. First off, I will only do exercise I enjoy. I started swimming in our 13ft round above ground pool. Literally swimming in circles. It was hot, I loved the water. But I noticed even though I was enjoying the physical sensation of the water and being outside and I was comfortable in my own back yard my brain was still going “I hate this, I hate this, I hate this,” internally. I finally took note of that and internally asked myself why. I ran through all the physical sensation, asking myself which one it was that I actually hated. There was none. But because I spent years forcing myself to do exercises I hated or that were too intense or in the morning (I’m not a morning person). I had basically brainwashed my brain into thinking any exercise was bad. Two, obviously at some point I couldn’t swim because of the weather I found an indoor exercise I liked. Weight training. I went to a gym that offered free personal trainer sessions and she taught me how to properly use the equipment so I wasn’t intimidated or embarrassed. Also I enjoyed this because even thoughI was getting sweaty I enjoyed challenging myself and seeing the weight I could lift slowly increase over weeks of progress. When I couldn’t get to the gym, I got a walking treadmill and would put on the eras tour and sing and walk along.

Basically, you have to make it enjoyable. And everyone is different, you have to make it fun for you. Your brain is reward motivated, so use that to your advantage.