Aerobic fitness is attained through exercises that improve endurance and stamina. Changes in the short-term and long-term performances of the heart and lungs are necessary for improvements in stamina and aerobic fitness. The roles of the heart and lungs in meeting the body's exercise-induced energy demands are examined.
In the article “ Primed for Fitness by Endurance and Stamina ”, it was shown that changes in the muscle that support improvements in endurance and stamina include increases in the capillary density of the muscles, and increases in the number of mitochondria in the myocytes (muscles cells). To power the aerobic activity of the muscles, delivery of oxygen and other nutrients is necessary. Removal of metabolic waste products is another necessary factor for sustained aerobic activity and aerobic fitness.
Respiratory Changes that Improve Stamina
The lungs are the primary organs for providing oxygen to the body from the atmosphere and removing carbon dioxide (a metabolic waste product) from the body. The need for performing this gas exchange quickly and effectively arises with increased physical activity.