Understanding the body: exercise and muscle isolation

By: Jet Rupar, LMT EP-C

Have you ever wondered, while you were at the gym doing bicep curls and wondering, “Does this really just work my bicep?” Or, maybe you’re doing a chest press and realizing that maybe it isn’t just working your pecs.

Very good questions, I am very glad that you have wondered this.

Yes, I have gotten these questions, and understanding what is going on when your working out is one of the things I love teaching people about.

The body never does anything “in isolation”. That being said, lets get some fun terms so we can all be on the same page.

There are muscles called Agonists. These muscles are the main muscles that activate when you go to move (and are also referred to as prime movers). When you are doing that bicep curl, your biceps muscle is the agonist in that movement… It is the main muscle in doing that bicep curl.

Synergists are muscles that work with the agonist to help create that movement. The Brachialis and Brachioradialis muscles help the Biceps muscle do that curl.

Antagonists (like in the movies) work against those prime movers and synergists. These muscles help to keep control and bring the body part back into neutral position. In the bicep curl, the antagonist is the triceps.

What do these terms have to do with muscle isolation??? This hopefully shows you that there is never such a thing as one muscle working totally by itself. It has the help of other muscles to so that movement can happen, whether you are working out in a gym, at home, or just walking through space.

Amazing, right?