Agonist - What Are the Agonist Muscles?

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If you know anything about your body and, if you exercise, I hope you do, you probably know that the muscles in the body are arranged in a certain way for you to be able to do all the movements you do in a day.

That is, your muscles are arranged in opposing pairs, at least in the torso, upper and lower body.  What that means is that, when one muscle is contracting, such as the chest muscle (well, there is more than one, but you get the picture), that muscle is called the agonist.

  While the chest muscle is working, there's an opposing muscle which is, also known as the antagonist muscle.

As you contract the chest, say during a chest press, you're actually stretching the back.  Think of this as you stretch.  If you lace your fingers together and stretch them forward as you round the back and you squeeze the chest, you'll feel a deep stretch in your upper back.

That means that, while your agonist is working, your antagonist can't work. This is called reciprocal innervation or reciprocal inhibition.  Say that three times fast.

The reason you need to know this?  Is because this is great information for putting together your own strength training workouts.

Opposing Muscle Groups

There are lots of ways to train your muscles and one is by opposing muscle groups, or agonist followed by antagonist.  This is one of my favorite methods of strength training because you do each exercise, one after the other, without rest.


The idea is that, while you're working the agonist muscle, the antagonist muscle is resting, so you can immediately go right to the opposing muscle group right after working the agonist muscle.  That's a great timesaver, something that makes finding time to exercise easier.

Sample Workout with Opposing Muscle Groups

There are a number of options for how your can set up a workout with opposing muscle groups.

  One option is to do an upper body opposing muscle group one day and a lower body opposing muscle group on different days. 

You can also split your workouts further like this:  Chest and back on one day, shoulders and legs on one day and then biceps and triceps.

Total Body with Opposing Muscle Groups

I really like to do opposing muscle group in a total body workout because, without the rest periods, you get added intensity without overworking any one muscle group.  The workout moves quickly because you're always doing and an exercise rather than resting.

Below is a sample total body workout with a focus on working agonists and antagonists.  You can do this in a variety of ways:

1.  Do each pair of exercises, one after the other, and repeat for 1-3 sets.  You would rest about 30-60 seconds between sets, shooting for about 8-16 reps of each exercise.

2.  Do each pair of exercises, on after the, other and go through the entire series of pairs, resting briefly between pairs.  This is a circuit style format that will keep your heart rate up and make the workout a bit more intense.

  You could do one circuit or up to 3, resting between circuits.  This is probably my favorite because the workout really flies by and it's over before you know it.

Focusing on your agonists and antagonist muscles is an excellent way to train your body.  You save time and you work all of your muscles so your body is balanced and strong.  Try it whenever you need a change in your routine and you'll find your body works in a different way.


American Council on Exercise. ACE Personal Trainer Manual, 5th Edition. San Diego: American Council on Exercise, 2014.

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