Your cardiorespiratory system is made up of your heart, blood vessels and lungs, or respiratory system. It's job is to circulate blood throughout the body, and when it doesn't function properly, your health is at risk, according to the American College of Sports Medicine. The long-term effects of exercise on this system are positive, and can lower your risk of disease while improving your quality of life.
When you're performing cardiovascular exercise, and even weight training, your cardiorespiratory system is affected. Any change in intensity of activity, like getting out of a chair, changes the needs of your body. Your heart and breathing rates increase most noticeably. This is due to the increased need for oxygen to the working muscles. The harder you exercise, the higher your breathing and heart rates. After exercise is complete these rates return to normal levels.
Maximal Cardiac Output
One of the most significant changes to the cardiorespiratory system is an increase in maximal cardiac output. This is a long-term change that occurs over time. Cardiac output is the amount of blood pumped by the heart in liters per minute, according to the National Strength and Conditioning Association. It's the result of stroke volume and heart rate. This long-term change is a result primarily of improved stroke volume, or the amount of blood that is pumped each beat of the heart. Basically your heart is stronger and can pump more blood in fewer beats.
Improved Oxygen Uptake
Oxygen-rich blood is pumped throughout your body constantly, and this increases during exercise. Oxygen uptake refers to the amount of oxygen that is taken from the blood and used by the muscles during exercise. A chronic adaptation is an improvement in this system. Over time your cardiorespiratory system becomes more efficient at getting oxygenated blood throughout your body, and the muscles become better at removing it and replacing it with carbon dioxide. This shows as an improvement in overall fitness, and lowers your risk of disease.
Respiratory adaptations are not as significant as the cardiovascular adaptations. Your resting breathing rate, or rate during intense exercise, does not change that much. Any changes that you notice are specific to each activity. For example, when you begin a jogging program you notice that you are breathing heavily and can only jog for 10 minutes. Over time it gets easier and you can jog longer and not breathe as heavily. This is an improvement specific to jogging, and it shows improved fitness, but does not translate to other activities.