My wife is a nurse in an intensive care unit. Last year, she suffered a back injury, and has gradually returned to almost full duty. (She has lifting and carrying restrictions placed on her by her physician, limiting the amount of weight she can lift and carry.) A few days ago, she was trying to roll an unresponsive 280 pound patient onto his side. In doing so, she strained her back, and was in pain for a couple of days. Is there a simple formula for us non-physics literate folks that would allow her to determine how much weight she is "lifting" in such a circumstance (i.e., rolling a heavy patient) based on the weight of the patient? This way, she could monitor her actions, and decline to be assigned a patient whose weight would result in exceeding the lift/carry restrictions when she has to roll him or her. Thanks so much in advance for the help.