When you exercise, your body has an increased need for oxygen. The working muscles need more oxygen to perform. Your heart and cardiovascular system responds by pumping out more oxygenated blood to the working muscles. Your respiratory system must also make adjustments to help meet the demands of the body during exercise.
Pulmonary System
Your respiratory system is comprised of your nose, mouth, lungs and air passages. It can be broken down into the conducting portions and the respiratory portions. The conducting portions are the passage ways into and out of the body. Whereas, the respiratory portion is where the actual exchange of gases occur. The primary function of the respiratory system is to provide a method of gas exchange between the air around you and the human body. Essentially this means to bring oxygen into the body for energy production and to remove carbon dioxide from the blood.
