"Occasionally revolutionary ideas disrupt the physical sciences. Such is the case with Power Factor Training." -- Flex magazine "After using the Power Factor Training system, I can't believe I ever used anything else. All the training I used in the past is now obsolete." -- Chris Duffy, Nationals Heavyweight Champion "Power Factor Training has picked up where Arthur Jones, Ellington Darden, and Mike Mentzer left off--and carried high-intensity training to its furthest possible level. I recommend it to all of my students who are interested in building maximum muscle mass--drug free!" --Dr. David Staplin, University of Minnesota In Power Factor Training: A Scientific Approach to Building Lean Muscle, bodybuilding and fitness pioneers Peter Sisco and John Little introduced a revolutionary new bodybuilding system that showed you how to develop your muscles to their fullest potential in the shortest time possible. Based on effective, scientifically proven principles of exercise, startling new research on recovery ability, and the importance of high intensity for stimulating muscle growth, the Power Factor Training system revealed how building a massively muscular body need not take years to accomplish. The response to Power Factor Training was overwhelming, so much so that readers demanded fuller Power Factor Training programs to isolate exercises for specific body parts. Power Factor Specialization: Abs & Legs provides exact, meaningful measurements for all shoulder exercises and back exercises and compares the intensity, or Power Factor, of each exercise. Complete with charts, graphs, and photos, this book enables you, at a glance, to see what exercises are truly the best (and which ones are the worst!) for stimulating maximum muscle growth in your shoulders and back. For example, for your back workout, why perform bent-arm dumbbell pullovers when they provide only 34 percent of the intensity of close-grip underhand chin-ups? offers a completely authoritative method for determining the muscle-stimulating benefits of every ab and leg workout you perform--with no more guesswork. It is now possible for you to determine exact exercises, weights, sets, and reps that you personally need to stimulate maximum muscle growth. You'll see immediate results from your first workout. Peter Sisco, editor of Ironman magazine's Ultimate Bodybuilding series, is the innovator of the Power Factor measurement of muscular intensity. John Little's articles have been published in every major bodybuilding and fitness magazine. The creator of the Static Contraction Training method, he is the editor of the Bruce Lee Library Series. Sisco and Little are the coauthors of Static Contraction Training and The Golfer's Two-Minute Workout, as well as Power Factor Specialization: Chest & Arms and Power Factor Specialization: Shoulders & Back. Bodybuilders and strength athletes in more than fifty-eight countries have used their techniques.