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Energy System Development Part 2

Dec 17, 2013

Energy System Development: Part Two

The human body utilizes three energy systems, the phosphocreatine, glycolytic and oxidative. Energy system development (ESD) is a form of training to focus on improved efficiency of individual/multiple energy systems. Variations in time and intensity will determine which energy system is being primarily utilized, with intensity being the more significant factor of the two. Intensity can be measured via a heart rate monitor or a rating of perceived exertion (RPE) scale. Time is measured in seconds/minutes with variations in the work to rest ratio and length of the work period determining which system is primarily being used.

Below, table 1 identifies the effect of event duration and intensity on the primary energy system used and table 2 indicates how using interval training to target specific energy systems can be implemented.

Table 1

* Baechle and Earle

Table 2

*Baechle and Earle

Different sports/events have different energy system demands and understanding which energy system(s) are primarily utilized is imperative for optimal training and performance; which leads us to next month’s blog which will cover the primary energy systems used for a wide variety of sports and events.


Baechle, T. R., & Earle, R. W. (2008). Essentials of strength training and conditioning . (3rd ed.). Campaign, IL: Human Kinetics.


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