Book Revier Build Muscle Without Weights

I was a "gym rat" in my teens, and early twenties and by the time I hit my 30's, I began to get joint problems, related to all my years of weight lifting. I am now in my 50's, and I have been using isometric exercise since my 40's. I am always looking for new exercise, and I happened to come across the title for this book, while doing a Bing search. It has turned out to be a great purchase, the exercise are clearly illustrated, and the exercise descriptions are easy to read. The shoulder workouts are a killer, my delts are screaming after doing them one day ago.
One note that I have discovered after dong these type of exercises for many years, everyone's body responds differently to exercise. It takes practice, to be able to simulate weight by using isometric tension. Breathing is especially important, I have found that my quads and shoulders respond best to these type of exercises in terms of definition, and muscle development. For the person who is new to these type of exercises, if you don't see immediate results, don't throw the book away, and quit, keep at it.