Sub-health

"Sub-health," isn't an actual term. You can say "a lack of health," "sub-par health," "poor health," etc. When I first read the title, I didn't know what to expect from the "Sub-health." I imagined a story about riding the subway or eating a sandwich haha. Hope this helps.

I am unfit/I need exercise Sub-health

I live and work in the city. From Monday to Friday, I often sit in front of my desk and use the computer to communicate with my customers. I haven't spent much time at the gym, and I think I'm unfit/not as healthy I I could be. Since I spent very little time on gym exercise, I think I am suffering from sub-health.