Pectoralis major, pecs for short, is your main chest muscle – pectoris being Latin for breast. Second only to the biceps in the muscle glamour stakes, this bodybuilder’s favourite has a number of important functions and as, in most gyms, Monday is ‘National pec Day’ training day, it’s well worth knowing how to keep your pectoralis major in good shape.


Pectoralis major, your primary upper body pushing muscle is, as the name suggests located on your chest and covers most of your upper body from the upper ribs to your collar bones and from your sternum out to your shoulders. It is a large, two part muscle (left and right – separated by your sternum) which is usually described as having an upper and lower portion.


The upper pecs, properly called the clavicular portion, has fibres that run upward toward the collar bones while the lower or sternal portion’s fibres run horizontally toward the mid and lower sternum. Both the sternal and clavicular parts of pectoralis major come together at a common insertion point on the front of the humerus or upper arm bone – just under the edge of the deltoids or shoulder muscle.


The main functions of pectoralis major are drawing your arm across your body, a movement called horizontal flexion and pulling your arms downward and inward into the midline of your body, a movement called adduction. In addition, it is also partially responsible for turning your upper arm inward – properly called medial rotation.

Pectoralis major is also an important shoulder stabiliser and prevents your shoulder joint being pushed backward. Because the pectoralis major can be separated, albeit figuratively rather than literally, into clavicular and sternal portions, it is possible to emphasise the sternal or the clavicular portions by varying the angle of your humerus.

Pushing downward or directly forward emphasises your sternal pecs while pushing upward at an angle of around 30-degrees emphasises your clavicular pecs. The steeper the angle, the less work the pecs do and the harder the deltoids must work. Once you are pressing vertically its deltoids all the way and the pecs are relegated to acting as shoulder stabilisers.

Activities involving pectoralis major

As you already know, your pecs are your main upper body pushing muscles. Pushing open a door, shoving an opposing player off the ball in rugby, punching and throwing are all good examples of the pecs in action. These movements also involve your triceps and deltoids where these muscles are acting as synergists (helper muscles) while the pecs are doing the majority of the heavy lifting.

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Problems associated with pectoralis major

There are a number of problems commonly associated with the pecs muscles. It is possible to ‘tear a pec’ when bench pressing very heavy weights – an injury not uncommon in the sport of powerlifting. Tears can be partial or complete – complete pec tears, properly called ruptures, normally require surgery.

Minor tears usually heal fairly quickly with rest. Tears usually happen at the musculo tendonous junction (MTJ) where the muscle morphs into a tendon and attaches to the bone. The most common location for pec tears is where the pecs meet the humerus.

“The other main problem associated with the pecs is overdevelopment or, more specifically, overdevelopment compared to the antagonistic or opposing muscles of the upper back.”

Overly tight pecs can have an adverse affect on shoulder joint function and is a very common problem. As the pecs are a medial rotator of the shoulder, if this muscle becomes overly tight, it can cause the humerus to turn inward so that your elbows naturally face outward rather than backward. This results in the ‘carrying rolls of carpet under your arms’ appearance so common with male gym goers.

Not only is this postural abnormality unattractive, it also adversely affects shoulder joint mechanics which can result in shoulder pain. To see if you are suffering from shoulder joint medial rotation, stand in front of a mirror and note the position of your hands when you let your arms hang naturally down by your sides.

If you can see your knuckles in the mirror, you are probably medially rotated. If you do suffer from this you need to stretch your pecs and work your upper back and external rotators more and maybe work less on your pecs until balance has been restored.

The other main problem associated with the pecs is overdevelopment or, more specifically, overdevelopment compared to the antagonistic or opposing muscles of the upper back. This front to back bias can further unbalance the shoulder joint and lead to yet more shoulder problems.

For this reason, every chest exercise should be counterbalanced with an exercise for the upper back such as wide-grip rows, band pull-aparts or face pulls.

Stretch and strengthen pectoralis major

There are lots of exercises you can use to get your pecs in great shape but here are a few of my favourite stretches and strengtheners that I keep on coming back to whenever I need a pec fitness fix…

Doorway chest stretch

Do this stretch every time you pass through an open doorway to quickly restore pec flexibility. Stand in an open doorway and raise your arms so your elbows are shoulderheight. Place your forearms and open palms against the vertical doorframes. Lean forward and push your chest between your arms.

Adopt a split stance for stability. Hold for 60 seconds or more. To increase the effectiveness of this stretch, push your elbows against the doorframe as hard as you can for 10 seconds and then relax. You should find you can now stretch more deeply. Do a couple of these contract/relax cycles and always end on a stretch.

Broomstick chest stretch

This passive stretch is not only a great pec stretch but an excellent postural exercise and also externally rotates your shoulders. Stand with your feet together, your chest up and your shoulders back – think tall! Take a broomstick and hold it across your lower back.

Grip an end in each hand so your palms are facing forward. Keeping your hands near the ends of the stick initially, push your elbows gently forward. Slide your hands a little closer together to increase the stretch. Keep your shoulders gently but firmly pulled back. Hold for 60 seconds or more.

“The bench press is THE classic barbell pec exercise and also a common test of strength. Entire books have been written about how to do this exercise properly and yet it’s arguably one of the most badly performed exercises around.”

Bench press

The bench press is the classic barbell pec exercise and also a common test of strength. Entire books have been written about how to do this exercise properly and yet it’s arguably one of the most badly performed exercises around. Rather than try and teach you how to bench press from scratch, here are twelve major technique tips you should try and follow to get the most out of this exercise…

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1. Plant your feet firmly on the floor – do not put your feet on the bench. If you cannot comfortably reach the floor, place your feet on a low step or stack of weight plates
2. Clench your bottom and keep it on the bench
3. Arch your lower back so there is a space between your back and the bench
4. Maintain your foot position and keep a tight bottom and back arch for your entire set – no fidgeting!
5. Think about pushing your chest up to meet the bar and push your shoulders hard into the bench
6. Grip the bar as hard as you can with a full grip – use your thumbs as well as your fingers
7. Grasp the bar so that your forearms are vertical when the bar is touching your chest
8. Inhale as you lower the bar toward your chest – this increases shoulder stability, intra abdominal pressure and also lessens the distance the bar has to travel
9. Lower the bar to the highest point of your chest – normally around nippleheight
10. Touch your chest lightly with the bar – imagine there is a plate of glass resting on your chest
11. Tuck your elbows in slightly – they should NOT be level with your shoulders
12. Exhale as you pass half way back up

Incline dumbbell flyes

Where most chest exercises are compound in nature, which means they involve movement at the elbow and shoulder simultaneously, dumbbell flyes are an isolation exercise which means movement only happens at one joint. By performing this (or any other) pec exercise on an incline, you emphasise the clavicular or upper pecs.

An angle of around 30-degrees is about right. Lie on your back and hold a dumbbell in each hand. Hold the weights over your shoulders with your palms facing inward. Bend your elbows slightly but then keep them rigid for the duration of your set. Open your arms and lower the weights out to the sides until your hands are roughly level with your shoulders and your arms form a sort of T-shape with your torso.

Squeeze the weights together and repeat. Because of the long levers involved in this exercise there is no need to use heavy weights. Focus on the movement and the muscles involved rather than trying to lift huge loads – leave that for your bench pressing!

Parallel bar dips

Performed using just your bodyweight or while wearing a weighted vest or weights strung around your waist, parallel bar dips are a great sternal or lower chest exercise – just look at the pec development of gymnasts for confirmation. With your hands on the bars, lift your chest and bend your legs so your feet are crossed and slightly behind you.

Bend your arms and lower your shoulders towards your hands as deeply as your shoulder health and flexibility allows. Push back up and repeat. Do not do bench dips in place of parallel bar dips – they are not even remotely comparable.

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