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Sylvester Stallone was seen dining at Craig's restaurant in Los Angeles on Wednesday. The 74-year-old actor is best known for his sensitive portrayal of a fictional boxer Rocky Balboa in the '70s Rocky film franchise.

Men with barrel chests typically have unusually large, round rib cages. The term "barrel chest" refers to a rounded chest that's shaped like a barrel.

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A barrel chest is not a disease, but it can indicate an underlying medical problem.

The rounded chest shape is caused by the rib cage naturally protruding as a man ages. It is typically seen in obese men and men who have an exaggerated forward rounding back (kyphosis).

Barrel chest can be caused by medical conditions such as chronic obstructive pulmonary disease (COPD), congestive heart failure (CHF), emphysema, chronic bronchitis, or osteoarthritis.

Barrel chest occurs because the lungs are overinflated with air, and the rib cage remains expanded rather than retract when a man exhales.

When the rib cage remains expanded or protruding, it can cause breathing irregularities and shortness of breath because air is trapped in the lungs and can't be fully expelled.

A barrel chest by itself does not require treatment. But it is a cause for concern if a barrel chest is accompanied by respiratory symptoms.

This has been your Medical Minute.