I cut the tendon that bends my middle finger. It’s been four weeks and my doctor still won’t allow me to really exercise it. Wouldn’t a good strength workout help my hand?

Working the finger muscles too soon after a surgery like yours puts the healing tendon at risk. Besides, gentle passive movements are proven to speed healing. Passive movements are done by moving the joint without the help of the muscles, for example, by bending and straightening the finger using your other hand. Putting force through the healing tendon has not been shown to make the healing time go any faster.