I know it can be stressful because I had two informational interviews, one with someone who held the position until he started upper division classes at college, and the current one who likes her work but feels she is "pigeonholing" herself by working in HR. It's a lot of paperwork, a lot of policy and law to learn, and you cannot fall behind. However, the training coordinator's boss is reputed to be easy to work with, and you do get trained in a workshop the first week.
I don't mind light physical labor. I routinely lift boxes in the 15-25 pound range, and as I am not that strong I have suffered with some back pain. I have learned how to pick up boxes more safely, and yoga has increased my flexibility so I am not in as much pain as I used to be. That said, I don't expect to be in this position forever, judging by my family's tendency to have knee and hip replacements.
I actually lose weight when I am stressed, which is not as good as it sounds. If I am severely stressed during a long period of time, I start looking anorexic. A more sedentary job would require me to exercise after work a little more, but that wouldn't be a big deal as I have a stationary bicycle at home and can always take a walk around the block. I would be on my feet some of the time as I would lead new employee orientation classes once a week for a few hours. But most of the time I would be sharing an office as opposed to logging a few miles of walking every day like I am doing right now. If I take the job and feel I am getting too sedentary, I could buy a bicycle and ride to work and back, if necessary. It's 15 minutes one way between my house and work.