Pectoralis major muscle facts for kids

The pectoralis major is a large, fan-shaped muscle. You can find it on the front of your chest. It's a very important muscle for moving your arms. Many people call it the "pecs" for short. This is because it's the biggest muscle on the surface of your chest.

What are the Pecs?

The pectoralis major is a strong muscle. It helps you do many daily activities. It's also very important in sports and bodybuilding. When people talk about "chest muscles," they are usually talking about the pectoralis major.

Where are the Pecs Located?

Your pectoralis major muscle covers a large part of your upper chest. It starts from your sternum (the breastbone in the middle of your chest). It also connects to your clavicle (collarbone). From there, it stretches across to your upper arm bone, called the humerus.

What Do the Pecs Do?

The pectoralis major has a few main jobs. It helps you move your arm in different ways.

• Bringing your arm across your body: Imagine giving someone a big hug. Your pecs help you bring your arm forward and across your chest. This movement is called adduction.
• Rotating your arm inward: This muscle also helps you turn your arm inward. For example, if you're doing a push-up, your pecs help push your body up.
• Lifting your arm forward: The upper part of your pecs helps you lift your arm forward. Think about reaching out to grab something in front of you.

Why are Pecs Important?

Your pectoralis major muscles are super important for everyday life. They help you push doors open. They also help you carry heavy bags. In sports, strong pecs are key for many actions.

• Throwing: Baseball pitchers and football quarterbacks use their pecs to throw balls with power.
• Pushing: Swimmers use their pecs to push water and move forward. Boxers use them to throw punches.
• Climbing: Rock climbers and gymnasts rely on their pecs for pulling and pushing movements.

Keeping your pecs strong helps you perform better in sports. It also helps you stay healthy and active.

Images for kids

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  Absence of sternocostal head of right pectoralis major associated with compensatory hypertrophy of latissimus dorsi is not rare. It is revealed on pressing downwards with the arms.

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  The function of the pectoralis major is different for its different heads. The clavicular head flexes the humerus, and the sternocostal head adducts the humerus. As a whole the action is to adduct and medially rotate the humerus. It also draws the scapula anteriorly and inferiorly.

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  Activation and protection of the Pectoralis major by a gymnast using talc.

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  Pectoralis major highlighted on the trunk – frontal view

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  Anterior surface of sternum and costal cartilages, showing origins

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  Left clavicle. Superior surface, showing origins.

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  Left clavicle. Inferior surface, showing origins.

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  Left humerus. Anterior view, showing insertion.

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  The axillary artery and its branches

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  The brachial artery

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  The right brachial plexus with its short branches, viewed from in front

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  The right brachial plexus (infraclavicular portion) in the axillary fossa; viewed from below and in front

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  Nerves of the left upper extremity

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  The left side of the thorax

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  Pectoralis major muscle

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  An individual with an abdominal portion of the pectoralis major, and an accessory sternalis muscle. Both these are anatomical variations.

See also

In Spanish: Músculo pectoral mayor para niños