Pitbull said...
If a person is under instruction from a PT and that person gets hurt, then I would say the PT is partially responsible as he/she has a duty of care to their client to ensure they are using the equipement correctly and within their physical means.
They are responsible, part of the registration fee for being a qualified personal trainer is insurance in case you hurt a client, least that's the way it worked when I was a PT.
PT's are wankers anyway, make em pay.