A hobby is good for your health. Just ask your doctor. . . . .a good balance in maintaining both.
This is precisely what balance means to me. There are days when I come home from work and go straight to the trains - after a day of meetings and crud at work I need to "de-compress." I can feel myself relax and "'become human" (or as close as I get) again, as my wife puts it.
Model trains are a great hobby for someone like me. They are their own self-contained world with a defined area and a clear boundary around them, both physically and emotionally. I can go there when I want, relax and be alone with my thoughts while distracting myself with a fun activity. Projects I can do challenge my creativity and modeling ability and tax my ability to innovate and invent, keeping me mentally on my toes, but are always fun. When I'm not feeling like being challenged, the trains are fun to run and watch - very relaxing actually. Yet, whenever I want or need, I can power everything down, turn off the lights, and leave it just where it is.