Chest/Pectorial (Pecs) Muscle
The pectoralis major muscle is the full name but better known in the gym world as pecs. They are two of the strongest muscles in the body and are very popular to develop.
LOCATION OF THE PECTORAL MUSCLES
These large muscles span across the front of the chest to the arm pits.
FUNCTION OF THE PECTORAL MUSCLES
The chest muscles are responsible for aiding movement and lifting in the shoulders and arms.
ABOUT THE CHEST
The chest is the ego muscle in the gym. People always ask "How much can you bench?" like it is the only factor of weather a guy is strong and lifts or not. In reality, building a sizeable pumped chest is acquired by getting the mind-muscle connection right - you won't build a gigantic chest by pressing serious weight if your shoulders and triceps carry most of the load. A big chest is also often down to genetics - some people, especially mesomorphs are naturally chest dominant and look like they train chest hard even when they don't.