If you persist with doing some of the exercises in this book, you will see results ( it can take months of doing them at least 5 times a week) The premise is correct - if you do not exercise your muscles they will get flabby and lose tone. But don't expect to get a 20 year old face back - any more than you can expect to get a 20 year old body back by doing exercise. However, it does help quite a bit to give your face a more toned look and reduce sagging. There are lots more exercises to be found on-line as well.
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The Yoga Face