Published On: Wed, Mar 8th, 2017

Working All The Various Parts of the Pectoral Major Muscle

As I started to read more about pushing weight, just when I think I understand it, I find out how much more there is to learn.  For the rookies like me, the chest muscle is the pectoral major and minor and all you have to do are bench presses.  Right?

Well, the chest is broken up as major and minor, but then it breaks down a bit further.  The pectoral major, the larger muscle that makes up the bulk of the chest muscle, is further broken down into the clavicular and sternalcostal [or just sternal] heads.  The clavicular head attaches to the clavicle [collar bone] and stretches to the humerus [arm bone], whereas the sternal head is attached to the sternum [breast bone] and stretches to the humerus.

Clavicular Head

The clavicular head is also called the upper chest.  When doing flat bench presses, the upper chest doesn’t get a lot of love like the lower chest muscles.  To really get them involved, you have to incline the bench.  I’m sure there are dozens of different exercises and variations, but I generally stick to these three:

  • Inclined Bench Press
  • Inclined Dumbbell Press
  • Inclined Dumbbell Flyes

I’ve read in several places to do reverse grip bench presses, but I’m not there yet, holding the bar in an awkward feeling way. One day.

The clavicular head is a stubborn muscle. Smaller muscles generally require a lot of attention to start to grow. To really develop the pectoral muscles, you want to go heavy. The exercise I do the most of the three is the inclined dumbbell press, but my heaviest pair of dumbbells are 30 pounds each. Ideally you want to find a weight where you come close to maxing out around 4 to 6 reps, but I can double that with the 30 pounders. But after looking at prices for heavier dumbbells, I might have to start focusing on the inclined bench press.

Inclined Dumbbell Muscles Worked
In addition to the clavicular head of the pectoral major, inclined dumbbell presses also engage the delts (shoulder), triceps, and lats (back).

Sternalcostal Head

So let’s see.  The chest muscles are broken down to major and minor.  And the pectoral major is broken into two heads.  The second head is the sternalcostal head, and it, too, breaks down even further.  Collectively it’s the lower chest, but it’s more accurately the middle and lower chest.

The middle chest are the pectoral major muscles that attach directly to the sternum.  The lower pec muscles attach to the costal cartilage of the rib cage.

Flat bench presses target these lower chest muscles, but to really get more even development, you want to change it up and add some declined bench presses to focus more on the lower lower chest muscles.  It’s not that flat bench presses don’t give the costal head of the pectoral muscles any work, just as the upper chest also gets a little attention, but the middle chest does most of the work, taking most of the benefits.

Of course the flat bench press should be complemented with flyes and dumbbell presses.  And dips and push ups, but I tend to avoid those.  For now.

One exercise that I have added to the routine is the dumbbell pullover.  It’s not really a fun lift, especially when your arms get tired while holding that huge dumbbell directly over your face.  The heaviest dumbbell I have is a 35 pounder, only one, and it gets heavy by the third set.  Especially since it’s one of the last exercises I do when my arms, chest and body are already giving in.

But it works the pectoral major muscles as well as the latissimus dorsi [back] muscles.

What I have to improve is the positioning of my elbows more when doing the bench press.  The arm should be at 45 degrees or a bit more from the body than tucked in too much.  But with all that weight over my body, I tend to forget to measure the angle.  When I do make a concerted effort to keep my elbows out, I can feel extra stretch when the bar comes down.

The more flared the elbows, the more focus is on the chest muscles, but it also increases the pressure on the shoulder muscles, and the last thing I want is for a shoulder muscle to rip.  For the most part, I do make it a point for the bar to touch down in the middle of my chest, around the nipples, rather than anywhere below, a sign that the elbows are probably tucked in too much.

Though some days my chest feels like it got hit with a sledgehammer, I’m determined to keep at it.  One day I want to be able to go to the beach and be a little less self-conscious when I go shirtless.  Of course, sooner or later I might also want to work on my bulging stomach smothering my abs.

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About the Author

David Gaines

- David Gaines is a Washington, DC, resident transplanted from North Carolina whose dream career was a newspaper writer but settled for the recruiting industry and simply blogging about whatever thoughts crosses his mind.


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