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3 Things You May Not Know About Your Body’s Energy Systems


Take a moment and think about what movements you do in your sport. Do you need to jump to grab that rebound? How about running across the field to score that winning goal? Perhaps swimming long distance in a 5k open water event. Each sport is unique because it requires certain intensity levels from the athlete. Our amazing body is adequately equipped to handle anything your sport throws at you with the right training. To avoid a boring exercise physiology lecture here are 3 things you may not have realized your body works to keep you moving.

3 Things You May Not Know About Your Energy Systems

Sprinter taking off from starting block
Sprinter taking off from starting block

1. Adenosine Triphosphate (ATP)

“Adeno-clean tri-what-rebate”? This hard to pronounce molecule is an extremely key part of the way your body is able to function and move. The food you consume is broken down and converted to ATP. Once converted, ATP is used as an energy transferring molecule to your body’s cells which include your muscles! This molecule once given up its energy ends up as adenosine diphosphate (ADP) which can be “recycled” back to ATP through a few different methods. Although ATP is the body’s high energy molecule there are only limited amounts at any given time. As a result three different energy systems are used in your body to help replenish ATP stores.

2. Three ATP “Engines”

The body rapidly uses ATP. Resupplying ATP is key for hard-working muscles. That’s where your body’s energy systems is key! Your body has three primary energy systems that have the ability to produce ATP. The three energy systems are:

  1. Phosphagen system
  2. Fast glycolysis
  3. Slow glycolysis

Each of these systems are beneficial only in specific intensities and durations. The Phosphagen system allows for a very quick and high ATP production. Think of a 100 meter dash. If highly intense exercises are required for longer, than the fast glycolysis system takes over. This engine would help produce ATP quickly for situations such as a 400 meter run. The third energy system in your body is the slow glycolysis. Slow glycolysis is most identified with movements that are not highly intense, but aerobic in nature. You can think of an open water swim or a marathon as a primary activity requiring the slow glycolysis energy system.

3. All 3 Energy Systems Work Simultaneously!

Although we have three energy systems with certain intensity preferences, the energy systems all work simultaneously. All systems are active and the level of intensity and duration of your activity favors a certain energy system. The Phosphagen system does not turn off when you are out doing an easy jog, rather it is less favored and the slow glycolysis system takes over.

Summary of 3 Things You Didn’t Know About Your Energy Systems

The study of bioenergetics is vast and never ending. Knowing how your body works provides insight into your workouts and athletics. At COR, we take careful consideration of the body’s energy systems, whether it’s at our boot camps, personal training sessions, or strength training for your sports team. We create safe and effective training programs to increase the efficiency and capacity of your body’s energy systems to help you achieve your personal goals.

Written by Jonathan Wong.