What Is Aerobic and
Anaerobic ExerciseThe working ability of a muscle
depends on sufficient blood flow,
oxygen and nutrition intake
The body uses two different systems to
supply energy to muscles:
Carbohydrates and fat are used with oxygen and metabolized to carbon
dioxide and water.
Anaerobic system: Carbohydrates are
used for energy production without oxygen and metabolized to lactic acid.
At lower training intensities, your muscles' use of oxygen matches your
oxygen intake. This kind of activity can be sustained for long periods of time.
At high intensities, however, your heart and lungs cannot supply enough oxygen
to keep up with the demands of your muscles. As a result, your muscles begin to
The problem with anaerobic energy production is
that after a few seconds, waste products like lactate rapidly build up. Lactate
blocks fat metabolism and forces the body to stop the exercise. The metabolic
turning point at which the body shifts from the aerobic to the anaerobic energy
system is called the anaerobic threshold (AT).
Your Anaerobic Threshold
(AT) is the exercise intensity at which you begin to go anaerobic and build up
lactate. If you want to improve your performance, it's useful to train for
short periods (three to five minutes) at a heart rate just below your AT in
order to raise it.
If you're out of shape, your AT might be at 70-80%
or less of your maximum heart rate. However, if your training progresses
intensively, your AT will increase, so that in very fit competitive athletes it
might be at 90% of their maximum heart rate.