Working out using your own body weight as resistance is by no means a new thing. Using your body instead of weights helps strengthen your whole body core which I consider from your knees to your shoulders. When I look at the biggest problems that end up causing people pain and discomfort as they age, most peoples problems come from a lack of strength in this full body core that I am talking about.
Here is a great full body circuit that you can add to your workout routine that will help strengthen your full body core and increase strength. If you add this in to your current workout routine regularly you will most likely save yourself from a lot of pain as you age. Click the link for instructions on how to do each exercise.
3 Sets of Each