“Exercise intensity is simply the amount of contraction that you generate in the working muscle per unit of time.
So the more contraction that you generate in the muscle per second, the harder the muscle is working, and the higher the intensity of the exercise. And thus, the greater the muscle growth is likely to be.”
If your goal is to build muscle, exercise intensity is, without a doubt, the most important factor in your workout plan. And that’s simply because exercise intensity is the #1 key to muscle growth stimulation.
So contrary to popular belief, it’s not “the number of reps that you do per set” that determines muscle growth. Nor is it “the number of sets that you do per exercise” that determines how muscle growth .
Ultimately, it’s the level of intensity that you generate in the working muscle, that determines whether or not an exercise will lead to greater muscle growth; and if so, how much muscle growth occurs.
And the higher the level of “intensity” generated in the working muscle, the greater the muscle growth stimulation is likely to be.
So the only way you’ll ever build maximum muscle naturally, especially “maximum muscle in minimum time”, is by achieving maximum intensity for any strength-training or weight-training exercise that you do. That’s how important exercise intensity is, in regards to building muscle!
The Role of Exercise Intensity, in the Process of Muscle Growth Stimulation
The crucial role that exercise intensity plays in the process of muscular hypertrophy (muscle growth) has been known for decades, going all the way back to research done in Germany a century ago. But amazingly, after all these years, nobody in history has ever offered us a correct, complete, practical definition for exercise intensity, as it relates to strength-training and muscle growth stimulation. Until now.
In this article, I do define exercise intensity correctly and completely. Finally! I know, it’s been a long time coming. At least 100 years, in fact! And there’s no doubt about it: defining exercise intensity correctly and completely is no easy task. Which is probably why nobody has ever done it before.
Nonetheless, I’m going to define exercise intensity so simply and so completely, that even a “retarded pig” will be able to understand and apply the concept; and thus reap the unique anabolic benefits that only strength-training done at a level of maximum intensity can provide.
And since this is probably the first and only time ever that exercise intensity has been defined adequately and made public, you’ll probably want to read all the way to the end. Especially if you want in on the secret that will enable you to build “maximum muscle in minimum time”; simply by doing weight-training exercises that take only 1-6 seconds each!
Where the Experts Got it Right on Exercise Intensity; and Where the Experts Got it Wrong!
Experts in the fields of strength training, weight-lifting, bodybuilding and exercise physiology have been unanimous about exercise intensity’s crucial role in inducing muscular hypertrophy for many years. Here’s how it works:
In order to get a muscle to grow bigger and stronger, you need to subject the muscle to a “higher level of intensity” than what the muscle is currently accustomed to. In other words, you need to get the muscle to “work harder” than what it’s currently used to. Doing so triggers an anabolic response in the central nervous system (CNS) that causes the muscle to “adapt” to that higher level of intensity. And the muscle does so by growing bigger and stronger.
Then once the muscle has grown accustomed to that level of exercise intensity, you need to go through the same process again, if you want to induce further muscle growth. You need to subject the muscle to an even higher level of intensity, thereby triggering another anabolic response in the central nervous system. And so on.
And the higher the level of exercise intensity that’s generated in the muscle, the greater the muscle growth is likely to be. So to build maximum muscle, especially “maximum muscle in minimum time”, you need to generate maximum intensity in the working muscle, for any strength-training or weight-training exercise that you do.
So intensity is the “trigger” that’s required to set the entire anabolic process in motion. If you don’t subject the muscle to a “higher level of intensity” than what it’s currently accustomed to, if you don’t get the muscle to “work harder” than what it’s currently used to doing, the muscle will have no reason to grow.
And this is true regardless of your diet, your hormone levels and balances, your genetics, how much high-quality sleep you get, how much stress you’re under, and other lifestyle factors that also play a significant role in the complete anabolic process.
The Rule of Progressive Intensity
In both Maximum Intensity Training (MIT), and Maximum Intensity Strength Training (MIST), what I’ve described above is called The Rule of Progressive Intensity. And that simply states that you need to subject your muscles to progressively higher levels of intensity, in order to induce progressively greater amounts of muscle growth and strength.
Where the Experts Got it Wrong on Exercise Intensity and Muscle Growth Stimulation
Now, what the experts are not unanimous about is this:
What is the fastest, most effective, most time-efficient, simplest and safest way to go about applying The Rule of Progressive Intensity, in order to achieve prolonged, sustained, maximum muscle growth?
Some experts recommend using a full range of motion done repeatedly (full-range reps), to accomplish that goal. Others recommend going only partially through your range of motion (partial reps). Others recommend static holds, or static contractions, with absolutely no motion at all. Some experts recommend that you lift fast; whereas others recommend that you lift super-slowly. Other experts recommend doing forced reps, negatives, and so on. Some experts even recommend that you limit yourself to compound exercises only, and shun isolation exercises entirely. Others recommend that you do only isolation exercises. And the list goes on.
So what’s the deal? Why all the confusion and disagreement?
The answer is simple: as I stated previously, nobody in the history of strength-training, weight-training or bodybuilding ever defined exercise intensity correctly and completely. Or if they did, they sure kept it a secret all those years!
So the correct definition for intensity was always the “missing piece of the puzzle”, in our quest for the ideal workout plan. And for decades, that’s what prevented even the experts in the field from developing the ideal, ultimate workout plan; one that would indeed give you “maximum results in minimum time”.
And to achieve maximum intensity, and thus maximum muscle growth, you obviously need to know what intensity is, as it relates to strength-training and muscle growth stimulation. You need a “working definition” for intensity, one that can readily be applied to any motion that you perform with weights; so that you can indeed achieve maximum intensity, and thus build maximum muscle, in the muscles that come into play for that particular motion.
And once you know that definition and apply it, you can achieve maximum intensity, and thus build “maximum muscle in minimum time”, from any motion that you do with weights.
And because intensity is inversely proportional to duration (the higher the intensity, the shorter the exercise has to be), you can accomplish that goal simply by doing exercises that take only 1-6 seconds each!
So what exactly is exercise intensity?
Muscular Contraction: the Key to Muscle Protein Synthesis
There’ve been many definitions for exercise intensity given to us over the years. Yet all of them have been either incorrect, incomplete or impractical. And that applies even to the ones given to us by the experts, in the fields of bodybuilding, strength-training, weight-training and exercise physiology.
One definition for exercise intensity that warrants close scrutiny, however, is one handed down to us by the late Mike Mentzer, one of the pro bodybuilding greats of the 20th century:
Mentzer defined exercise intensity as being “the percentage of your maximum, momentary, muscular effort” that’s exerted, when performing an exercise.
So in other words, Mentzer was saying that “the more muscular effort you exert per second“, the higher the intensity of the exercise. And thus, the greater the muscle growth stimulation is likely to be.
Mike Mentzer’s definition for intensity is actually one of the best that’s been given to us. But when it comes to practical application, it has limitations. And that’s because Mentzer didn’t specify exactly what he meant by the word “effort”.
So what exactly is “effort”? And how can you quantize effort, to determine if your “momentary effort” is greater than, the same as, or less than what it was, the last time you did that particular exercise?
Effort can actually mean three different things. Effort can mean:
1) the energy expended to perform the task at hand
2) an attempt to perform the task at hand
3) the immediate result of the energy expended or the attempt made, to perform the task at hand
So which one of those three did Mike Mentzer mean? Well, we can bypass #1 and #2, since there’s no way for you to measure or quantize either of those.
Now if we consider #3, that leads us to this question:
What is the immediate result of the “energy expended” or the “attempt made”, when you perform a strength-training or weight-training exercise?
Isn’t it muscular contraction? Isn’t “muscular contraction” your primary, immediate objective behind all that pushing, pulling, swinging and lifting you’re doing, when performing any strength-training or weight-lifting exercise? Don’t you have to contract your muscles to get them to “work harder”, so that they can grow bigger and stronger?
Yes, of course! So if we substitute the word contraction for the word effort in Mike Mentzer’s definition for intensity we get the following:
“Exercise intensity is the percentage of your maximum, momentary, muscular contraction that’s generated, when you’re performing an exercise.”
So the more momentary, muscular contraction that you generate in the working muscle when performing an exercise, the higher the intensity of the exercise. And thus, the greater the muscle growth is likely to be.
And although this modified version of Mike Mentzer’s definition for exercise intensity isn’t quite complete yet, it certainly gives us a much more useful and practical definition for exercise intensity than Mentzer’s original version.
So how do we expand on this definition for intensity, to make it even more useful and practical? Read on, to find out more.
You Don’t Need Reps to Build Muscle; What You Do Need is Muscular Contraction
Basically, exercise intensity is a measure of “how hard” the exercising muscle is working. So in order to get a muscle to grow bigger and stronger, you need to get the muscle to “work harder” than what it’s currently used to. And the harder you get the muscle to work, the higher the intensity of the exercise; and thus the greater the muscle growth stimulation is likely to be.
So what is the ultimate measure of “muscular work”? How do you know if a muscle is working as hard as it possibly can or not? In other words, how do you know if you’re generating “maximum exercise intensity” in the working muscle or not?
Well, most people erroneously believe that in order for a muscle to perform work, it also has to be doing some kind of motion. But the truth is that although motion is required to perform mechanical work, motion is not required at all for the metabolic work done by a muscle. And the metabolic work executed by the muscle is what’s important, when it comes to muscle growth.
In fact, generally the “more motion” a muscle executes per unit of time, the “less hard” the muscle is actually working! And thus, the lower the muscle growth is likely to be. So remember that whenever you workout.
For example: imagine holding a 100 lb. barbell in place in the palms of your hands, both arms bent, forearms parallel to the ground, with absolutely no motion. You’re simply doing a “static hold”, halfway through the biceps curl. Is there any motion? No, none at all. Are your biceps working? Of course! You’re biceps have to be working, in order to hold the weight in place. And the heavier the weight is, the harder your biceps have to work, in order to hold the weight in place; even in the absence of motion.
So let’s get this straight: contrary to what you’ve probably heard and read over and over, you don’t need to do “repeated body motions” (a.k.a. “reps”) to build muscle.
We know this to be true without a doubt, because you can build muscle simply by doing isometrics. And isometric exercises involve no motion at all. For that matter, you can even build some muscle just by flexing your muscles. And that would involve no motion either. Case closed.
What you do need to build muscle is contraction. Muscular contraction is the underlying factor behind the effectiveness of all muscle-building exercises. This is true, whether you do full-range reps, partial reps, static holds or contractions with weights, isometrics (which involve no weights), or simply flexing your muscles.
Sure, you can build muscle by doing repeated body motions (reps). In fact, you can actually build a lot of muscle by doing reps. Just be aware of the fact that you’re not building muscle because of the motion. You’re building muscle due to the contraction that’s occurring in your muscle, as you do the motion.
So the fact is, muscular contraction is what induces ‘muscle growth stimulation’, that leads to muscle protein synthesis (muscle growth). Motion, per se, has nothing to do with the process.
So remember: when you bend your arm, or straighten your leg, or do any body motion, muscular contraction is what causes the motion. The motion does not cause the muscular contraction.
And since muscular contraction is the key to muscle growth, it should come as no surprise to learn that the more contraction that you generate in the working muscle throughout an exercise, the higher the intensity is likely to be. And thus, the more muscle growth you’re likely to induce.
With that said, you can generate a lot of contraction in a muscle when doing an exercise, but you still might not experience any muscle growth from it. And as far as your actual workout plan goes, that could be due to two reasons:
1) The level of intensity that you generated wasn’t any higher than what the muscle is currently accustomed to, regardless of the amount of contraction generated. So as a result, there was no stimulus generated in the central nervous system (CNS), to trigger the process that leads to greater muscle growth.
2) All that contraction was spread out over too long a period of time.
And that brings us to the other part of the equation, the one that’s missing from most definitions for exercise intensity: time.
Time: the Missing Factor in Most Definitions for Exercise Intensity
Any correct, complete, practical definition for exercise intensity has to include the “time factor”. If it doesn’t, that means the definition is incomplete, and probably inapplicable. At least for the purpose of achieving maximum intensity and muscle growth. Or even for the purpose of achieving high intensity.
And that’s because it’s not just the “amount of contraction” that you generate in the muscle that determines the intensity of the exercise, and it’s effectiveness in regards to inducing muscle growth. It’s the “amount of contraction” that you generate per unit of time that determines the intensity of the exercise; and thus it’s effectiveness in regards to greater muscle growth.
In fact, one good thing about Mike Mentzer’s definition for exercise intensity is that it does include the “time factor”. And it does so by using the word momentary.
And that finally brings us to the correct, complete definition for exercise intensity.
Exercise Intensity Defined, Correctly and Completely
Simply stated, exercise intensity is determined by “the amount of contraction that’s generated in the working muscle per unit of time“.
This explains why sprinting is a higher-intensity exercise than jogging is. When you’re sprinting, you’re running as fast as you can. And that requires that you generate “more contraction per unit of time (i.e. per second)” in your leg muscles than you would have to do when jogging, where you just take your time.
And since “intensity is inversely proportional to duration” (the higher the intensity of an exercise, the shorter the duration has to be), this is also why sprinting has to be much shorter in duration than jogging would have to be. Nobody can sprint for a long period of time.
And we can easily apply that definition for exercise intensity to strength-training or weight-training, to get the following:
The intensity of any strength-training exercise is determined by “the amount of contraction that’s generated in the working muscle per unit of time“, as the muscle works against a net external force (a.k.a. resistance); such as that provided by a weight.
So the more contraction that you generate in the muscle per second, the higher the exercise intensity is at that point in time. And thus the greater the muscle growth stimulation is likely to be.
So: MAXIMUM INTENSITY=MAXIMUM MUSCULAR CONTRACTION per SECOND=MAXIMUM MUSCLE GROWTH STIMULATION
With that in mind, you need to know that there are actually two types of contraction that are important for strength-training and building muscle. And in order to generate “maximum muscular contraction per second” and thus achieve maximum muscle growth, you obviously need to maximize both types of contraction simultaneously, throughout the entire exercise.
And as we get into those two types of contraction, another important, yet usually unanswered question arises:what exactly is muscular contraction?
Obviously, you need to know what “muscular contraction” is, in order to maximize those two types of contraction simultaneously, and thus generate “maximum muscular contraction per unit of time”.
To learn the answer to that question, and to learn about the two types of contraction required to achieve maximum intensity and build maximum muscle, please read the follow-up article to this one:
Comments? Questions? Care to agree or disagree? Feel free to do so!