Chest muscles, or pectorals, are the muscles in the upper chest. They create a movement for the shoulder joints and help to protect the ribcage by forming a strong connective tissue between each of its ribs.
Chest muscles are used in many activities, such as swimming, rowing, throwing a ball, lifting weights, etc.
These muscles can be strengthened by carrying out certain exercises, such as push-ups. These will help to make your chest muscles firmer and stronger over time, which will result in an increased lung capacity. By increasing your lung capacity, you can improve sports performance.