How often have you heard or read about dynamic contraction? Probably not very often, if at all. In fact, this massive series of articles on “exercise intensity” may be your very first introduction to the term. And that’s because other than Maximum Intensity Training (MIT) and Maximum Intensity Strength Training (MIST), I’m not aware of any workout plans that even use the term dynamic contraction.
Nonetheless, dynamic contraction (DC), specifically maximum dynamic contraction “per unit of time”, is essential to triggering the anabolic process that can lead to maximum muscle growth. Because as I explained in the first article of this series, Exercise Intensity: the #1 Key to Building Muscle, Part I; Exercise Intensity Defined, exercise intensity is “the amount of contraction generated in the working muscle, per unit of time“.
And as I explained in the second article of this series, Exercise Intensity: the #1 Key to Building Muscle, Part II; Muscular Contraction Defined, there are two types of contraction that you need to maximize, in order to achieve maximum intensity; and thus maximum muscle growth. And dynamic contraction is one of them.
So how do you generate maximum dynamic contraction in the working muscle, when performing any strength-training or weight-training exercise?
How to Generate Maximum Dynamic Contraction (DC) in a Muscle
Dynamic contraction is the type of muscular contraction that causes motion. So dynamic contraction simply refers to the process whereby a muscle contracts by “shortening”, usually in order to move a body part towards the working muscle. This is called the concentric phase of motion.
Imagine bending your arm with no added weight, so that your forearm moves toward your biceps. What enables you to perform that motion? It’s dynamic contraction. Obviously, you have to “activate” (i.e. “contract”) muscle fibers in your biceps to move the forearm towards the biceps. And as you do so, the amount of dynamic contraction in the biceps gradually increases.
And when the forearm is as close as it can get to the biceps and can move no farther, and you’ve reached the end of the concentric phase of motion, you have maximum dynamic contraction (DC) in the biceps, for that particular type of motion (i.e. bending the arm). And that’s your only point of maximum dynamic contraction in the biceps in your entire range of motion, for that type of motion.
So remember: every point in your range of motion has a different amount of dynamic contraction. And, since intensity is the “amount of muscular contraction that you generate per unit of time”, you want to generate as much dynamic contraction as you can per second; in order to increase the intensity of any weight-training exercise that you do.
And because maximum dynamic contraction (DC) is a requirement for achieving maximum intensity, you need to get to your point of maximum dynamic contraction (DC) when you’re weight-training, in order to achieve maximum intensity and maximum muscle growth. And thus, it’s the only point in your range of motion where you have the potential to induce maximum protein synthesis, in the muscle fibers that are recruited for that particular motion.
Also, remember that whenever you perform reps (repetitions, or “repeated body motions”) of any kind, the amount of dynamic contraction (DC) constantly fluctuates; sometimes dropping down to zero. And that, of course, causes the intensity to constantly fluctuate; sometimes dropping down to zero.
Where Conventional Weight Training Exercises Fall Short on Dynamic Contraction
Amazingly, some of the most popular and highly-touted conventional weight-training exercises limit your range of motion so much, that it’s impossible to get to your points of maximum dynamic contraction (DC). And that’s why you’ll never achieve maximum intensity, or build maximum muscle from those exercises.
Those exercises include the lat pulldown, the overhead press, the dumbbell fly, the lateral raise, the front raise, the pull-up, and even the bench press, and the squat!
So it’s always ironic to hear people talk about using a “full range of motion” for the bench press, when there’s really no such thing. It’s impossible to use a full range of motion when doing the bench press. In fact, you can’t even come close.
Your range of motion when doing the bench press is actually so small, that it’s akin to doing the biceps curl and lifting the weight up only about 2-3 inches, and then lowering it. Do you think you’d ever build maximum muscle in your biceps by doing the biceps curl like that? No way! Likewise, you won’t build maximum muscle in your pectoral muscles by doing the bench press either.
So basically, you’re actually doing “partial reps” whenever you do the bench press; although most people (even experts and personal trainers) are unaware of this fact. Furthermore, those partial reps are limited to your “weak range” of motion. And that’s where you have the least amount of dynamic contraction (DC), and the lowest potential for maximum muscle growth.
And if you are going to opt for partial reps for this particular type of motion (i.e. the one that works your pectoral muscles, when you do the bench press), you’d be much better off doing the partial reps in your “strong range” of motion, where you generate the most dynamic contraction. That way, you can at least generate “more contraction per unit of time”, and thus a “higher level of intensity“; and thus achieve more muscle growth, than you would by doing the partial reps in your weak range of motion.
For more on that, read my article, The Overrated Bench Press: Dethroning the King of Chest Exercises
So now that dynamic contraction has been covered in this article, how do you generate maximum resistance-induced contraction (RC) in the working muscle, when performing any weight-training exercise?
That’s a lot more complicated than achieving maximum dynamic contraction (DC), due to several variables that come into play. But I make it as easy-to- understand as I can in the follow-up article to this one:
Comments? Questions? Care to agree or disagree? Feel free to do so!