Your Heart and Lungs:
An Introduction to Cardiorespiratory Physiology Breathing is not usually something we think about until it becomes difficult . If you cannot get a breath, it becomes very prominent on your mind. We do not normally notice our breathing until we are “out of breath” from hard physical exertion. Then, for a short while, we breathe heavily and breathing goes unnoticed until the next hard effort.
Likewise, we seldom think about our heartbeat. The heart just beats by itself. There are very few things that create as much anxiety as chest pains that could be due to heart problems. Heart palpitations tend to be scary. We may not have to think in order for our heart and lungs to work, but anytime we are under physical or emotional stress, we become very aware ofthe importance ofour heart and lungs.
The heart and lungs combine with the arteries, veins and capillaries to make up the cardiorespiratory system. The heart, arteries, veins and capillaries combined are often referred to as the cardiovascular system. Cardio refers to the heart and vascular refers to the blood vessels.
The cardiovascular system is responsible for transporting blood throughout the body. The blood that is transported through the cardiovascular system carries the nutrients the body needs to function. The lungs are the site where the body gets rid ofcarbon dioxide and takes up oxygen. This process is called respiration.
The respiratory system includes the lungs, airways and the diaphragm. The efficiency of the cardiorespiratory system influences one’s ability to obtain and utilize oxygen to generate energy. Individuals who seem able to run all day long have not only trained their slow-twitch fibers to be efficient, but they have also trained their cardiorespiratory system to be efficient at obtaining and extracting oxygen while getting rid of carbon dioxide (which becomes toxic if allowed to build up in the body).
On the opposite end of the training spectrum, one ofthe primary signs of heart and lung diseases is becoming winded with mild exertion. Individuals with heart or lung disease often become fatigued when performing day-to-day tasks that most of us take for granted.
Exercise training can help, except for highly progressed cases which may have gone beyond the point of repair without surgical or other medical intervention. (Anyone suspected of heart or lung disease or exhibiting shortness of breath with or without mild exertion should be referred to a physician immediately.)
Cardiorespiratory conditioning can be as simple as walking or taking the stairs, or as strenuous as running a marathon. The key point is to have the functionality to do the things that you want to do. Our focus is on the underlying structures that ensure that the body gets the oxygen it needs and gets rid of carbon dioxide before it builds up to toxic levels.
Knowledge in cardiorespiratory physiology will assist you in understanding the adaptations that occur with training and how to develop training programs that elicit these adaptations.
Cardiorespiratory function refers to the ability of the heart to pump oxygen rich blood throughout the body. You may be more accustomed to the term cardiovascular which refers only to the heart, blood vessels and blood. Working together, the cardiovascular and respiratory (lungs, alveoli, airways and diaphragm) systems deliver oxygen-rich blood and nutrients to the body. Together, these two systems bring nutrients and oxygen to the muscles and other systems of the body and then remove wastes such as carbon dioxide and lactic acid. Ultimately, it is the oxygen transport along with the ability of specific muscles to generate ATP aerobically that will determine the maximal level of aerobic energy released during strenuous activity.