 Now, if you look at the major muscle groups in the body, the hip and thighs, chest, upper back, bicep, shoulders, delts, and whatnot, it does not actually require a lot of different movements to involve all those muscles. If you were to perform a push and a pull and a multi-joint hip and thigh movement, you would have pretty much hit almost every single muscle in the body, adding a push and a pull in another direction, for example, doing a vertical or a horizontal push and pull and a vertical push and pull just kind of rounds things out a little bit better, but it doesn't take a lot of exercise. For example, if you look at biceps, upper back, back of the shoulders, it's not necessary to go and do a rolling movement or a pullover for your upper back and then add a bent over fly for your rear delts and a shrug for your traps and then a dozen different types of curls for your biceps and broccoli alice and broccoli radii alice and whatnot. If you do a row, every single one of those muscles is involved and if you're doing it hard enough, all of those are going to be involved to enough of a degree that you're going to stimulate about as much improvement as you possibly can. By trying to do a lot of different exercises, this exercise for the specific muscle, that exercise for that specific muscle and so on and so forth, what a lot of people end up doing is holding back so that they're capable of performing more exercises. So although they might be able to work everything individually and isolate this muscle, that muscle, they're not actually getting nearly as much out of the workout. One, because they've compromised intensity for the sake of adding all these different exercises, two, because in doing so, even if they are working the actual muscles separately, any time you perform an exercise, in addition to the local effect, the effect on the specific muscles that work, you're going to have a systemic effect. The damage to the muscles that occurs is followed by an inflammatory response and that's cumulative. The more exercise you do, the greater this response and it's part of what contributes to overturning. Eventually you get to a point where if you've done enough of this and you've done it too much within a particular timeframe, you start to have flu-like symptoms, basically this inflammatory response is affecting your nervous system in a way that's trying to make you slow down and back off. So you don't want, you don't need to do a bunch of different muscles for all the different muscle groups or exercises for all the different muscle groups. If we take chin up, for example. If you did nothing but chin ups or pull downs, you get your biceps, your forearms, upper back, back of your shoulders, traps, bunch of different things there. If you were to do nothing but that exercise and over time build up to the point where you're doing pull downs with double your body weight or you're doing chin ups with your body weight plus another 50, 60 pounds hanging off of you, even if you had never done a single isolation exercise for your biceps, they would have become much, much larger and the same would go for doing an exercise like dips, bench presses, shoulder presses and the triceps. You're not going to be able to progress and wait over time in these exercises without all of the muscles involved becoming larger. Some people talk about weak links and compound movements. For example, claiming that if you're doing a chest exercise, your triceps are always going to fail before your pecs or your shoulders or whatnot. Now, if you're performing the exercise properly, everything is going to be worked to approximately the same degree. The only time that you're going to see disproportionate involvement to those muscles is if you are specifically changing the way you're performing the exercise to change the leverages involved. I'm not going to get into that a whole lot because I know that Bill's going to talk more about the biomechanics tomorrow, but a real quick example in the case of doing, say, a chest press. If you grip the bar with about a shoulder width or slightly wider hand spacing, the positioning is such that as you're going through the movement, the moment arms or the levers or the difficulty encountered by the different muscles involved is going to be somewhat proportional to where all of those muscles involved are going to experience a similar amount of work. If you feel like your triceps are going before your chest, chances are you're using too narrow of a grip. In fact, some people will specifically use a very narrow grip doing a bench press because it changes the leverage in such a way that your triceps have to work a lot harder. If your grip is too wide, you're going to feel more chest, more shoulder, less tricep. If you look at what's happening, the closer in, the more tricep, the further out, the more chest. At some point in between those is a grip where everything that's involved is going to be working roughly equally proportional to their capability. Another way to look at it is we would not have developed or evolved the muscular system that we have in a way that you have any one particular muscle group that is a limiting factor for the others. If such was the case, we'd have a little bit different leverages, different musculoskeletal geometry because it would make no sense to have a certain amount of strength in your upper back muscles if you couldn't apply it in regular activities because of a weakness of the biceps or grip. So again, it does not take a lot of exercise to effectively work all the major muscle groups in the body. Like Doug mentioned again, if you're doing a push and a pull both in a horizontal and a vertical plane and doing a multi-joint leg movement, you're pretty much hitting everything.