I concur. I had incredible joint pain and stiffness while working an overnight call centre job early in my life. No social life, no sports, no physical activity... I literally quite and went on their disability program, it was so bad.

Except, while on disability I rotated around to regular hours, started doing social and eventually sports things... And, what do you know? Turns out I'm fine --it is just that being strapped to a chair with four active customer support conversations going at once for eight hours every day was literally causing my joints to lock up due to inactivity (or similar).

Went to uni and found a career that kept me more active. Now I get my 10k steps just idly doing my job.