Help! My Left Pec Is Bigger Than My Right, What Should I Do?

left pec bigger

The thing you have to remember is not to panic. This is a common occurrence and one that will remedy itself over time. Remember to be patient and to continue training as usual and this slight problem will usually even itself out in a couple of months.

This phenomenon usually occurs for those aspiring weight trainers who are just starting out and one that is quite common in the weight training world. The way I look at it, some parts of your body are more adept to strength and coordination because of body preference.

For example, when I first started out training, my left arm was always stronger than my right. It was also bigger by about a half an inch. It didn't matter if I was curling a barbell or bench pressing, my left arm was always to one to power through the movement. My right arm was always the first to give out.

For awhile, I didn't know what to think and I was getting very frustrated with the whole thing. After thinking about it for awhile, I came to realize that my right arm didn't have the “experience” that my left arm did. That is, when I was growing up, I used my left arm for just about everything. From playing hockey to throwing a ball, it was my left arm that did most of the work.

So, it was only natural that my body depended on the strongest arm to power through a lot of my upper body movements.

The same can be said for most of your muscle groups. You may find that your right leg is stronger than your left or your left shoulder is stronger in pressing movements than your right. You may also notice that some muscle groups are larger than their corresponding muscle “partners” such as the left and right biceps.

The thing you have to remember is that this is only a temporary thing. Over time, your weak body part will have no choice but to become stronger and more coordinated. It will grow, to match that of your stronger side.

However, if you don't want to wait a couple of months, you can do some extra work for your weak muscle group. For example, let's say your left pec is bigger than your right and you want to correct that problem sooner than later. In this case, you may want to do a little extra work for the left pec. Let's say you're doing dumbbell bench presses for 3 sets of 10. On your last two sets, you might want to do an extra rep or two for your right pec.

The same can be done for most of your exercises such as biceps curls, leg presses, dumbbell shoulder press and other exercises. Just remember to add an extra rep or two for your weak body part and you should see an improvement in a couple of weeks or so.

Remember, this is not a permanent thing and one that will remedy itself in a couple of months. Keep on doing what you're doing and be patient.

Need help?

Do you need help putting your diet and training program together? Do you need help finding out what you need to be doing to lose 10, 20 or even 40 pounds of body weight? Do you need help gaining body mass or strength? Do you need help finding the right program for your goals? Let me know and I'll tell you what you need to be doing to reach your goals. This is a FREE SERVICE and I'm more than willing to help. Just go to this page here and fill out the online form and hit submit. I'll get back to you ASAP (I won't collect your email address or spam you). Just ask me your question and I'll answer it - Blake

Good luck and all the best,


As the owner of Building Muscle 101, I am committed to providing you the best practical weight training advice. I've been training for over 24 years (and still train to this day!) and the advice and guidance I provide comes directly from my experience and knowledge.

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