Why aren't double chin exercises possible?

In a young person, a "double chin" is usually the result of fat between the skin and the platysma muscle.  This can be removed easily with liposuction often done with local anesthesia only.

Think about it this way.  Just because you are exercising your neck muscles does not mean that you are losing fat from your neck.  It may help to tone the muscles and make them stronger, but it also does not mean that you are changing the shape of the muscle.

You need to feel comfortable with the recommendations of your physician.  Go ahead and try the neck exercises as long as you want.  We will be here to help you when you realize that it is not giving you the results that you want or expect.