[Ziggythecat]

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You have a case against both the negligent person who left the treadmill running (probably covered by homeowner's or renter's insurance) and would have a case against the gym, but only if the gym knew or should have known the treadmill was left running. The gym likely has a legal duty to inspect for dangerous circumstances occurring within the gym and the longer the treadmill had been running, the better your case. If it was a short time frame, the gym may not be legally liable, but the gym might have insurance that could pay some of your medical bills. You should consult with a local lawyer.

here's another:

Apparently the individual who was using the treadmill had stepped off for some strange reason without turning the treadmill off. She did not notice the machine running. The treadmills are very quite and also with all the other treadmills all in line of more than 20 or so, and other people using them, it is very easy not to notice a running treadmill. Not to mention, who in his right mind leaves a "run a away treadmill"? Needless to say she fell and injured herself. According to some of the patrons, who witnessed the fall, we have a pretty good idea who the careless individual was.