Aerobic conditioning

Aerobic conditioning is a process whereby the heart and lungs are trained to pump blood more efficiently, allowing more oxygen to be delivered to muscles and organs. The skeletal muscles also become aerobically conditioned, as regular aerobic exercise produces a shift in muscle fibres from more type II (fast twitch/glycolytic) into more type I (slow-twitch/oxidative). Type I muscle fibres have far more mitochondria than type II, making type I fibres the producers of adenosine triphosphate (ATP) primarily through oxidative phosphorylation rather than anaerobic glycolysis. Some neuromuscular diseases recommend regular aerobic exercise (of varying intensities depending on the disease) in order for the skeletal muscles to become aerobically conditioned, providing relief of symptoms or slowing the course of the disease, for example metabolic myopathies and Duchenne muscular dystrophy.

Aerobic conditioning is the use of continuous, rhythmic movement of large muscle groups to strengthen the heart and lungs (cardiovascular system). Improvement in aerobic conditioning occurs when athletes expose themselves to an increase in oxygen uptake and metabolism, but to keep this level of aerobic conditioning, the athletes must keep or progressively increase their training to increase their aerobic conditioning.

Aerobic conditioning is usually achieved through cardiovascular exercise such as running, swimming, aerobics, etc. A stronger heart does not pump more blood by beating faster but by beating more efficiently, primarily by having an increased stroke volume and left ventricular mass. Trained endurance athletes can have resting heart rates as low as the reported 28 beats per minute in people such as Miguel Indurain or 32 beats per minute of Lance Armstrong, both of whom were professional cyclists at the highest level.