One of the bad things to do as a worker especially in the medical field is the bend-lift-twist  movement, a sure way to hurt your back. The most common example is bending over a patient and then lifting him to scoot him up towards the head of the bed. To avoid injury, make sure you: call for assistance, raise the bed up so you won't bend and do the scooting in synchronized manner. Best of all, do core exercises like pilates.