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Over the past few weeks, I’ve been getting many questions from trainers at my gym about Exercise Selection.

“Why do you pick the exercise you do? How does exercise “A” compare to exercise “B?” Isn’t (blank) exercise the better choice?”

Selecting exercises for a workout program involves much more thought than most people and trainers tend to give to the process. There should never be an exercise arbitrarily picked just because it’s “your favorite exercise” or some public figure says (blank) exercise is awesome. More understanding of anatomy, biomechanics, myology and the goal need to be factored in.


To over simplify a very complex subject, every muscle in the body has a stretched (lengthened) position, a contracted (shortened) position, and a relatively neutral (natural) position. Every muscle in the body is also the WEAKEST at both its longest position and its shortest position. If we train a muscle in these weaker positions and the ranges around them, the muscle has a lot more room for growth and development. This means that your gains will come significantly quicker because you are improving the weakest areas of the muscle. You’re only as strong as your weakest links so bring those bad boys up!

Attacking Exercise Selection from this perspective gives each of the exercises you program for you or your clients a purpose. You now know that one exercise must get the muscle in a shortened position and one exercise must get the muscle in a lengthened position. This is why it’s useful as a gym-goer and imperative as a trainer to understand anatomy, biomechanics, and myology.

Let me note here that, YES, this does mean that you only have to do 2 exercises per muscle every time you train that muscle. NO, I’m not saying that you can’t do more than two exercises. I’m just saying that you must incorporate at least one exercise that takes care of the shortened position and one exercise that takes care of the lengthened position. Outside of that, you can include whatever you want or add nothing further.


Let’s look at the hamstrings. The hamstrings cross over both the knee and hip joint. If you want the muscle short (think "fully contracted") you need to be in hip extension and knee flexion. If you want the muscle long (think "stretched") you need to be in hip flexion and knee extension. To give you visuals of these positions, I have picked the lying hamstring curl which allows the hamstring to get into a fully shortened position and the seated hamstring curl which allows the hamstring in get into a fully lengthened position.

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There are a few exercises that you can pick that will put you into these profiles. With that said, certain exercises will overload these two positions differently. This is where the “goals” of a workout or program need to be taken into account.


There are different stimuli that we can create in the gym to elicit different responses from the body. The type of stimuli you want to evoke will play a role in exercise selection. Regardless of the stimuli, YOU STILL NEED AT LEAST ONE EXERCISE IN THE SHORTENED POSITION AND ONE IN THE LENGTHENED POSITION.

In the lengthen position, you have a shorter micro position and a longer micro position.

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In the shortened position, you have a shorter micro position and a longer micro position.

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The stimuli you chose determines which of these micro positions you will want to overload. Different exercises will load certain micro positions better.


Though there are many different stimuli to choose from, let's just look at two.

In mechanical damage, we’re trying to shred as many muscle fibers as possible. This happens more often when the muscle is lengthened (think “stretched”). The weakest of muscle fibers will not be able to handle the loaded stretch and they will be the first to get damaged (in a good way). This means that, if we are trying to produce mechanical damage in a muscle, we need to pick two exercises that overload the longer micro positions more than they load shorter micro positions. Two exercise that will do this are stiff leg deadlifts (lengthened hamstring position) and ball hamstring curl (shortened hamstring position with butt up). Both of these exercise are more intense when the muscle is in the longer micro position. Stiff leg deadlifts are easy at the top when standing up but difficult at the bottom in the stretch. The ball hamstring curl gets easier as you bring your heels to your butt but becomes more intense as you straighten your legs (butt stays contracted and off ground the entire time). We have loaded the long micro positions in both hamstring exercises. Thus, more mechanical damage will be produced.

In metabolic damage, we’re trying to make the muscle burn as much as possible. This happens more often when the muscle is shortened. Concentric contractions produce lactic acid. The harder you contract, the more “burn” you will feel. The shorter you can make the muscle, the harder the contraction can be. This means that if we are trying to produce metabolic damage, we need to pick two exercises that overload the shorter micro position more than they load the longer micro position. Two exercises that can do this are the seated hamstring curl and the lying down hamstring curl (depending on the machine’s resistance profile). On both of these machines, you can generate hard contractions in the shorter micro positions. Adding a band on both the seated curl and lying curl can produce even more resistance in the short micro position of both exercises. Thus, more metabolic damage as long as your muscles can handle it.


When it comes to exercise selection, more thought needs to be involved. Anatomy, biomechanics, myology, and the goal need to be factored in. It’s not enough to choose exercises that you like. The exercises you choose need to be deliberate and correspond with the goal. Including exercises that put a muscle in a lengthen position and a shortened position are ideal for muscle growth and development. In fact, training in only these two positions and understanding stimuli is how I deliver staggering results in a mere three 30 minute sessions each week for my clients.

Want to experience this first hand? Come train with me! Click here to sign up for a free fitness assessment.

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