 And over a period of a couple seconds, a little bit harder and a little harder until you're contracting as hard as you possibly can, and then you gradually ease off, you're not going to wreck yourself in the process, you're not going to pull or strain anything. In either case, it's a tremendously heavy weight, but whether you hurt yourself depends on the manner in which you attempt to lift it. And you want to move similarly during an exercise. You have to lift heavy. If the weight is not adequately heavy, it's not going to do you any good. No amount of lifting with light weight is going to produce any kind of meaning for results. And it comes down to that intensity, the level of effort that you put into the exercise. It's an absolute, but if you're going to do this for the long run, if you're going to be doing this when you're in your 40s, 50s, 60s, I know some people in their 70s and 80s that train in this fashion, you have to do so in a manner that's not going to wreck your joints in the process. So you need to keep in mind when you're doing these exercises that you have to always be moving under control. Again, with the example of picking up or attempting to pick up a car, if you take the weight and you try to yank or jerk at it as fast as you can, you're going to pull or strain something. If on the other hand, you attempt to lift it gradually, and as you approach the end of the lifting movement, you gradually sort of stop, you reverse direction, you bring it back down, you anticipate reaching the start. You slow down for that so that you're able to reverse direction smoothly. You'll be able to lift as heavy a weight as your muscles are capable of, but you're not going to pull, strain, wreck, or damage anything in the process. In a healthy person, your tendons, your ligaments, your other connective tissues, everything will be able to more than adequately handle the heaviest weight that your muscles are capable of contracting against, and as long as you're moving in a strict and controlled fashion. The other thing that tends to stop people from pushing as hard or pulling as hard as they possibly can during exercise is physical pain or fear of physical pain. For most people, the exercise stops when it starts to become uncomfortable. If you look at a lot of people in a gym, if a person is really going all out, by the time they get to the point where they are at their actual physical limits, they will have slowed down considerably. A person who can comfortably curl at a moderate pace if they're using a heavy enough weight, their last repetition is going to look like this. They're just going to be barely moving it. Watch a lot of people, their speed doesn't change too much. They get to a point where it starts to get uncomfortable. They set it down. The problem with that is the point where you start to become uncomfortable is those last couple of most productive reps where you reach that point Doug was talking about where you're sending the message to your body that it is about to die or it thinks it's about to die. If you stop when it starts to burn, if you stop when it starts to become uncomfortable, you are stopping right at the point where the real exercise begins. Now again, keep in mind that you're not going to injure yourself if you're moving in a controlled manner. The burn is not an indication that any kind of actual large-scale physical damage is being done. Now there is damage, very, very small damage. You have little tears, it's called microtrauma, a structural level. Galactic acid Doug discussed is going to have some effect on that discomfort too, but there is no kind of real injury occurring. Now something that helps is if you keep in mind the difference between pain which is informative. Pain is basically telling you that, hey, something is wrong and doing so so that you stop doing whatever is causing the damage and what is called exertional discomfort which is actually what's happening during exercise which is non-informative. It doesn't tell you anything you don't already know. Your muscles are working hard, okay? We already know that, but there's nothing, again, there's nothing happening there that's going to cause any damage. You can safely ignore that. If you also consider as you're getting to that point that the exercise is temporary and what's happening is not suggesting an injury that's going to persist afterwards, that helps you be able to push through that, but one of the things that seems to be most effective is if you look at it, the burn, that discomfort that occurs during exercise, rather than an indication that you're getting towards the end of the exercise, but as a cue that it's time to start working harder, it helps you push through that. For example, leg extension, which if anybody has done any heavy, heavy training, anybody here do leg extensions or has done leg extensions part of workout. It's one of the worst as far as sensitivity. For some reason, people tend to feel it in their frontal thighs, some people calves more than anything else and on almost more than any other exercise, I see people quitting on the leg extension before they've gotten anywhere near what they're actually physically capable of because of that burn. It is, well, it's just downright painful. People stop because they're worried about hurting themselves. People stop because it's extremely uncomfortable, but again, that burning means that you're getting towards the most beneficial, the most important part of the exercise and rather than stop at that point, you should consider it your cue to push even a little bit harder. Something else that makes a big difference is having some external motivation. Having somebody else there to push you doesn't have to be a trainer, but even if it's just a friend, somebody else in the gym, as most people will push themselves, nowhere near their limits. But if you have somebody else there, even if it's just trying to impress somebody else in the gym or somebody who is going to push you, it makes all the difference in the world. But that's as far as the intensity is concerned. Those last couple repetitions are the absolute most important in an exercise. What you're trying to do is send a message to your body that its current ability is inadequate to meet some demand that your environment is placing on it. If you're capable of an all-out effort completing 10 repetitions and you were to stop at 7 or 8, you're not asking your body to do anything that it already isn't capable of. It's less likely to expend any resources to produce an increase in muscle mass, or any other metabolic adaptation, which can be expensive. You have to give it a good reason to do so. It's only when you attempt that 10th repetition and even when you get to a point where it's no longer possible to continue, you keep contracting against it that you're really telling your body, hey, we need to be stronger. We need to be better capable of tolerating this so that the next time we encounter it, we're able to successfully complete whatever it is. In the case of an exercise, the exercise, or as far as your body knows, again, you could be fighting a bear or a tiger or something. As far as the amount of exercise, we're balancing it against the intensity of exercise. You have to train hard for the exercise to be effective, but, again, doing so is going to limit the amount of exercise that you can do. Most people think you've got to do dozens of sets of bunches of different exercises for all the different muscle groups. If you read muscle magazines, most bodybuilding or fitness books, they'll have routines that'll typically involve three to four sets of anywhere from three to sometimes five or six exercises per muscle group. Anybody who's capable of completing a routine like that is not working anywhere near as hard as necessary to get the maximal benefit from the exercise. In fact, if a person is training as hard as I'm talking about, pushing to your absolute limit, and then at that point continuing to attempt to push for a couple seconds, you're not going to be able to tolerate a very large amount of exercise at all. And like Doug mentioned, workouts last around 8 to 12 minutes. Mine, a little bit longer, not because I spend more time doing the exercise, but because where I'm working out, I'm using barbells, so there's time in between that I have to have to switch out the place. But where I'm using machines where I can just pull and switch a pin, my workouts would probably be pretty similar to Doug's in length. And I don't do just that much because I don't like working out, or don't do that much because I'm in a rush, but because I am not physically capable of doing any more exercise than that when I'm done. 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 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 rowing 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 brachialis and brachioradialis 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.