The three system used for energy production (ATP) in the body are the phosphagen system, glycolysis, and the oxidative system.
- The phosphagen system provides energy for activities lasting 0-6 seconds.G
- Glycolysis produces energy for activities lasting 6 seconds to 3 minutes.
- The oxidative system supplies energy for activities lasting 3 or more minutes.
While each energy system can be active at any given time, the contribution of each to energy production is dependent primarily on the intensity of the activity and secondarily on the duration.