Energy Systems Explained: Shedding Light on Anatomy Revision

Energy Systems are a tricky topic to get your head around. In today’s blog, we will shed light on how energy is created using candles. This will teach you an easy way to learn and remember the three energy systems ready for your anatomy exam.

It’s a bit like the way candles burn.

Let’s take a closer look at the three main energy systems you need to know for your Level 2 and 3 Anatomy Exam… and we’ll use candles to keep it simple.

Imagine you have three candles burning, each representing a different 3 energy system:

  1. Aerobic (The long burner)
  2. Lactic Acid (The medium burn time)
  3. and Phosphocreatine (the tea light).

Watch Energy Systems Explained: Shedding Light on Anatomy Revision

Energy Systems Explained: Shedding Light on Anatomy Revision

What are the three energy systems?

We have three main energy systems in our body, each creating Adenoisine Tri-Phosphate (ATP). All three systems work under different environmental conditions and circumstances.

These three energy systems work all the time in our body to create ATP so that we can move, digest, survive… and live.

The Phosphocreatine System: Quick Energy

Think of lighting a small tea-light candle. It gives off a bright flame but doesn’t last long.

That’s similar to the Phosphocreatine (PCr) system. It is also known as the Creatine Phosphate (CP) System.

It gives you a quick burst of energy for short, intense activities like sprinting or lifting something heavy for a few seconds.

But, like the tea light, it burns out in about 10 seconds.

Cardiovascular activities that use this energy system will access the highest heart rates between 90% MHR and 100% MHR. These feature short bursts of high-intensity exercise (sprints), followed by rest that allows the heart rate to recover. This is particularly effective for speed improvement goals.

The PCr system is also used for the initial stages of most movement. Imagine moving quickly to catch a can of beans from falling out of a cupboard. This is an instant burst of energy fuelled by the PCr System.

The Lactic Acid System: Steady Burning

Now, picture a candle burning steadily but gradually getting smaller.

That’s like the lactic acid system.

It kicks in for activities lasting from 10 seconds to 3 minutes, such as sprinting or doing resistance training.

Cardiovascular activities that use this energy system will access higher heart rates between 80% MHR and 90% MHR.

It provides energy efficiently but the waste products are fatiguing, which creates a limit as to how long it can be used before rest is required.

Imagine running on a treadmill, you’ve increased the speed to the point whereby you can maintain a conversation. You can feel that the pace is unsustainable. You might manage 1 minute or maybe as much as 3 minutes before the lactate accumulation in the blood is too great. At this point, your breathing rate has increased considerably as you fight to get more oxygen in.

Eventually, you give in and have to reduce speed on the treadmill so you can “catch your breath”. The oxygen you take onboard buffers away the build-up of waste products and allows you to recover. This means after a few minutes (depending on fitness levels) you can increase the pace again.

This approach is called an Anaerobic interval. You are moving between the Anaerobic lactate system (that doesn’t need oxygen) and then resting at an aerobic intensity.

The amount of time you spend in each interval and the number of interval repetitions you can tolerate are key indicators of VO2max/ fitness levels

The Aerobic System: Consistent Energy

Lastly, imagine a candle burning steadily in the background, providing a constant glow.

That’s the aerobic system. It gives you energy for activities lasting more than three minutes, like jogging or cycling.

It relies on oxygen and breaks down carbs and fats to keep you going.

See this as the “long burner” candle with many hours of burning time available.

Most of our daily lives will use this energy system as a means of creating ATP. This is because oxygen, carbohydrates and fats are usually readily available.

Understanding How Energy Systems Work Together

While each energy system works on its own, they also work together depending on what your body needs. Just like candles burning at the same time, your body switches between energy systems as you move. Whether you’re sprinting, lifting weights, or doing a long workout, your body adapts to use the right energy source.

Shedding Light on Energy Systems

Thinking about energy systems like candles helps us understand how our bodies work. Whether it’s the quick energy of the Phosphocreatine system, the steady burn of the Lactic Acid system, or the lasting energy of the Aerobic system, they all play important roles in keeping us moving and functioning.

Test your knowledge with today’s Energy System mock questions:

[NOTE: The answers are below the 3rd question]

Q1: Which energy system is predominantly used in a Marathon?
A. Adenosine Triphosphate
B. Lactic Acid System
C. Aerobic System
D. Phosphocreatine System (PCr)

Q2: How can you tell your client is training in an anaerobic energy system?
A. Unable to talk, breathing is faster and signs of fatigue
B. Can keep a conversation going easily
C. Breathing rate is reduced and the client feels fresh
D. Able to talk, breathing rate is reduced

Q3: Which Energy System has fatiguing Bi-Products?
A. Adenosine Triphosphate
B. Lactic Acid System
C. Aerobic System
D. Phosphocreatine System (PCr)

Answers to the mock questions are :

Question 1= C, Question 2 = A, Question 3 = B

If you want more mock questions like this, then you can download more Free Mock Questions: DOWNLOAD NOW

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Hayley “Energy Systems Explained: Shedding Light on Anatomy Revision” Bergman

Parallel Coaching

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