I actually feel this same way often. On my days off I will get everything done, house chores, errands, and then I will be bored out my mind. I will look for more work to do even though I want to relax. I often feel like there is something I should be doing even though it's probably all in my head. Sometimes I will read a book or play a videogame to help keep my brain occupied. It is very hard for me to just be idle.
Fortunately, I have various religious observances to keep me active, but I find too much of that wears me out too. I like to be busy. It's when I'm idle that I end up smoking and drinking.
I can relate to this. I love weight lifting and when I discovered high intensity training I was hooked, but it took a long time to really get comfortable with the fact that if I did HIT I couldn't do it more than 2x/week (MAX!) if I wanted to get good results. Doing it 2x/week wasn't an option if I was doing any kind of physically demanding MA training at the same time, and even at once a week I had to time it right with my MA training, especially as I got older. I've found that I can focus on skill development training without causing my body significant stress. This is easier with some arts than others, but I can usually find something that I can practice that's more brain work than hard physical work, but still has a low intensity, physical, component. I also do a lot of walking when I'm feeling like I need more recovery but still want to do something physical. It's healthy, it gets me outdoors and away from screens, I find it mentally relaxing, and my wife will often go with me and it gives us great, uninterrupted time to just chat and be together.
