I usually run outside and frankly, trip and fall once every six weeks or so. I never break anything and usually just wind up with a bloody knee or elbow. However, because of a broken bone in my foot I could not run at all for 4 months. The doctor suggested I get back into it by running on a treadmill. On my second run, I started to fall three times after tripping on the belt, but each time I inadvertently tripped the STOP with my flailing arms. Once, however, I actually went all the way down and flew off the back. Funny, I know, until I landed on a machine. Why does this happen? Am I just not picking my feet up high enough? Should I run more consciously?