Calorie and Energy Expenditure Information
Anaerobic Exercise Workout
What is Anaerobic Exercise?
In simple terms, activity fuelled by oxygen is called aerobic exercise, whereas activity fuelled by non-oxygen sources of energy is called anaerobic.
The Anaerobic Energy System
During the first two minutes of exercise, the body cannot get enough oxygen to supply the heart and muscles which need to work faster than normal. So the body uses two non-oxygen sources of energy: (1) the ATP-PC system, and (2) Anaerobic Glycolysis. These two anaerobic systems - called anaerobic metabolism - are relied upon exclusively during short, intense activities like: the 100-meter sprint, shot-put, high-jump and all weight-lifting.
Anaerobic ATP-PC System and Exercise
This system supplies instant energy. It uses an ATP (adenosine triphosphate) molecule, an energy-rich unit, made up of adenosine and three phosphate groups. ATP provides enough energy for muscles to contract maximally for about 15 seconds. However, if an activity needs repeated muscular contractions for longer than this, the energy must be sourced from other stores, like glycogen.
Anaerobic Glycolysis and Exercise
Anaerobic glycolysis is the fast supply of energy from the breakdown of stored glycogen in the muscles. (Glycogen is stored blood-glucose.) If this anaerobic metabolic process continues in the absence of sufficient oxygen (from breathing), it produces a bi-product called lactic acid. This lactic acid can build up in the muscles and blood, causing fatigue. Often during the first few minutes of strenuous activity, you may experience burning in the muscles of your arms, legs or back. This is due to the creation of lactic acid.
Anaerobic then Aerobic
If you exercise continuously for longer than about 2 minutes, you eventually burn up all of the glycogen stored within the muscles and, as your breathing generates more oxygen, your muscles will move into aerobic metabolism. When this occurs lactic acid production is stopped and the remaining lactic acid is removed via the bloodstream. Provided you continue to breathe correctly, oxygen will continue to supply the muscles and the aerobic process will continue.
For information about the calorie content of popular food and drinks, please visit: Calories in Food
Energy Expenditure and Calorie-Burning