Avoid clothes that restrict your mobility such as tight trousers. This can encourage bad posture and back stress. Avoid or minimize the use of high heel shoes. If you must wear heels, save them for special occasions. Wheel your belongings.
Briefcases are heavy.
So are big purses slung on shoulder straps. Dangling from one shoulder, those big loads create an unequal stress on your spine, which can hurt your back. You can do some common sense techniques to minimize back strain. Carry the minimum in a purse.