Cardiovascular System
The cardiovascular system involves the heart, the lungs,
and the extensive network of arteries and veins that transport
materials throughout the body.
A major area of study in exercise physiology is the function of this
system to deliver oxygen to all working tissue and to remove carbon
dioxide from working tissue.
The ratio of oxygen consumed to carbon dioxide produced is the primary
measure of the body's efficiency (or cardio fitness) level. The
more fit an individual is, the more efficient the body is in making
oxygen available to the working tissue and in removing carbon dioxide.
More efficient systems have
a lower heart rate,
a higher stroke volume,
and a more well developed vascular system,
especially a greater number of capillaries.
Why?