Have you ever had one of those moments when you suddenly decide you want to dedicate all your workouts to a certain muscle group? In my case, such bursts of resolve usually stem from seeing a particularly beautiful example of said muscle groups at a party or the gym.

gay fit guy

In one instance, I saw an amazing model at a bar in New York City with the most beautiful pecs. Immediately determined, I decided that I too could, and should, display equally amazing chest muscles. So, I cycled through every pec exercise I could come up with for the next two months. I would add a chest exercise at the end of every circuit, often hitting it 4 or 5 times per week. Within a few months, I had noticeably bigger pecs. Yet, there was a problem. My posture got much worse, and I started to experience back pain.

I had no idea what was causing the issue until my physical therapist commented that my body was imbalanced. My traps, delts, and rhomboids were disproportionately small compared to my pecs. He noted that my overdeveloped pecs pulled my shoulders in towards my midline and made my back slouch. Unless I counteracted the force generated by my pecs by developing my traps, rhomboids, and deltoids, I could do long-term harm to my posture. He did some cupping to relieve tension in my back and help my posture.

Cupping on back

Balanced Workouts-The 4 Muscle Types

Looking back, it makes total sense. It’s clear to me that one should exercise the left side of the body as much as the right. But it took a physical therapist’s insight for me to grasp that one should seek balance on other planes as well, such as front to back.

In NASM Chapter 4, I learned that all major muscle groups contain the following muscle types:

  • Agonists work as the prime mover of a joint exercise.
  • Synergists assist the prime mover in a joint action.
  • Antagonists oppose the prime movers.
  • Stabilizers minimize unwanted movement while the agonists and synergists work to provide movement to a joint.

The aptly named agonist does all the work. In my example, my pecs fill the role of my agonist when they push the heavy barbell away from my chest. The antagonist stands ready to provide counterbalancing force if for some reason the barbell was being pushed towards my chest. Yet, I only pushed things away from me so I could get big pecs, and never pulled things toward me (rows) to engage my traps, delts and rhomboids (pec antagonists).

Every time you exercise an agonist, you should do something to engage the antagonists as well. Here are the primary agonist/antagonist muscle pairings:

Antagonistic Muscle Group ListSynergists are all the smaller muscles surrounding the major muscles to perform their primary movement. Stabilizer muscles are those that make up your core. They provide stability and leverage for joint actions. Without a strong core, your mobility will be weakened.

The Complex Work of a Personal Trainer

As I learn about the various factors that go into designing balanced workouts, I’m more and more impressed with the work of personal trainers. Workouts have to juggle so many dimensions at once, such as the choices between anaerobic and aerobic exercise, weight versus reps, high and low intensity, which muscle groups to target, how to engage agonists and antagonists, and how to involve all planes of motion. There is a lot more to be mindful of than I initially thought.

This complexity highlights a few key points for me:

  • The importance of treating exercise like a practiced skill. It takes theory, repetition, instruction, and study to become good at working out. It’s simple to take the first steps but can get increasingly complex the more you know.
  • The primacy of balance. It’s a theme I keep coming back to as I progress in my physical training journey. The body needs, seeks, creates, and thrives in a state of balance.
  • Opposition is healthy. If we only moved in one direction with no challenge, half of ourselves would wither away. Opposition creates strength.

Follow Jacob’s journey to becoming a personal trainer here.