This video describes how to exercise in such way to maintain or promote defined chest muscles. It is explained that the chest muscles should be worked hard enough to actually gain muscle mass. Next, it is explained that muscle mass is lost as you age and the skin loses elasticity. The video explains how to counteract the effects by building muscle to maintain a defined appearance. The video describes that chest exercises should be done in sets of 5-8 reps. The video next explains that when performing the exercise the muscles should be contracted fully but only allowed to relax about two-thirds of the way; the video says that four or five sets of such exercises will build muscle. An altered fly exercise is explained and demonstrated next; the weight for the reps should be such that you can only do about 8 repetitions.