Lesson 3: The 2 Energy Systems (Aerobic & Anaerobic)
December 20, 2009 by mbluestone94
In order to sustain life we must fuel the processes which enable it, just as you must fuel your car for it to operate. We
will now discuss the two energy systems and how your body interchangeably uses them to turn the food you consume into energy it expends. This energy is known as “adenosine triphosphate” or ATP and both energy systems produce ATP; however they do so in unique ways. The first and most applied means of producing ATP is termed “aerobic.” The second and least utilized production of ATP is termed “anaerobic”
Aerobic Energy is produced through activity that requires a constant and adequate supply of oxygen. Examples of aerobic activities range from sleeping to light exercises which do not inhibit shortness of breath.
Anaerobic Energy is produced through activity that does not require oxygen (short duration and high intensity). Examples of anaerobic activity are sprints, high intensity circuit training, and anything else which cannot be sustained for greater than 30-60 seconds before fatigue, shortness of breath, and or nausea sets in.
We will now discuss how both the aerobic and anaerobic energy systems produce and use adenosine triphosphate or ATP.
Aerobic Energy System
Aerobic exercise demands the body takes oxygen into the lungs, to the blood where it is then pumped to the working muscles. At this point the oxygen oxidizes carbohydrates (in the form of glycogen) and fats which create the production of energy and is termed the oxidative system. Aerobic pathways provide the major supply of energy to all cells of the body. If your goal is to reduce body fat then you will be relieved to know that one of the favorable characteristics of the aerobic energy pathways is its ability to utilize stored body fat as a primary source of energy. You will also be happy to know that you are in an aerobic state even at rest.
Did you know that when you are at rest your body feeds off of stored body fat and nothing else? Rest is a vital component of fitness and often not enforced enough.
You may be asking “why should I even bother with anaerobic activity if the aerobic system burns the fat?”
Answer: If you stick with purely aerobic exercises you will soon find yourself on a plateau and possibly lose the ambition to exercise. A plateau will occur because of the body’s tremendous ability to adapt to frequently imposed demands. It’s a built in safety mechanism which we can’t turn off via the power of the mind; therefore we must trick it by turning on the anaerobic energy system periodically for short bouts not exceeding 60 seconds. This unfamiliar and strenuous exercise will cause the body to learn new adaptations. We will discuss how to integrate the two energy systems in the lesson titled program design. Let’s move onto the anaerobic system.
Anaerobic Energy System
In order to start the anaerobic system you must begin with the aerobic system. As the heart rate elevates, it is progressively working harder to deliver a sufficient amount of oxygen to the muscles to produce enough ATP aerobically. At some point (varies according to fitness level and genetics) the cardiovascular system is unable to supply enough oxygen to the exercising muscles, forcing them to convert from the aerobic system to the anaerobic system to produce ATP (energy) rapidly. Instead of metabolizing both carbohydrates and fats, the anaerobic system will rely on glucose (material carbohydrates are stored in) and for prolonged high intensities; it will also use creatine phosphate energy for about 10 seconds before extreme fatigue onsets.
IMPORTANT: you should know that when your body switches from the aerobic energy system to the anaerobic system you have reached what is known as the anaerobic threshold or lactic threshold.
Summary:
If you are overwhelmed with this lesson do not fear! All you need to know is that aerobic is activity conducted with the use of oxygen and anaerobic is high intensity activity conducted without oxygen. Both energy systems are vital for progressive results.
Due to the body’s ability to adapt to frequently imposed demands we must continuously create new challenges for the body and its systems, in this case we are creating new challenges for the cardiorespiratory system and the muscles used to perform the exercise. This means that if you continue to conduct the same or similar exercise routines your body will no longer progress; in fact it may even regress.
Have you ever been consistent with a cardio routine and there were days when your body felt tired, preventing a desired pace? This is because of burn out which is the result of an ineffective use of the two energy systems, aerobic and anaerobic.
Continue to the lesson 4 titled heart rate training zones to learn more about heart rate training formulas. During this lesson you will learn when you are conducting aerobic and anaerobic exercise. Relax…we will get to cardiorespiratory program design shortly but first I want to teach you how your body works.
Course Directory:
Beginning: Introduction To Cardio Respiratory Fitness 101
Lesson 1: The purpose of cardiorespiratory training
Lesson 2: Primary cardiorespiratory measurements
Lesson 3: The two energy systems: aerobic and anaerobic
Lesson 4: Heart rate training zones
Lesson 5: Interval training using personal heart rate training zones
Lesson 6: Cardiorespiratory assessments used to determine an appropriate stage for you
Lesson 7: Cardiorespiratory program design (choose the one that matches your goal):
[...] Lesson 3: The two energy systems: aerobic and anaerobic [...]
[...] Lesson 3: The two energy systems: aerobic and anaerobic [...]
[...] Lesson 3: The two energy systems: aerobic and anaerobic [...]
[...] Lesson 3: The two energy systems: aerobic and anaerobic [...]