| I started off at ~65-70 lbs overweight, and while its not 100 lbs, I was still able to start jogging right away without any joint pain at all. Of course I could onlyl run 3/4 of a mile my first try, and am only now up to 1.5 miles, and I can run for almost 20 minutes non-stop.
I think if you normally have joint pain you would likely increase it with running, if you normally have no joint problems you would probably be ok. | 
