The mechanics of energy

What is energy? What happens in our body to make us feel energetic or fatigued?

energy yoga

There are many factors that influence our energy and its levels. Our metabolism, nutrition and hormones are the biggest key players. In this article I’m going to focus on our metabolism, our energy source ATP and the role of nutrition. 

What is energy?

I don’t mean in the metaphysical sense but in the actual physical, real sense. Energy, that allows us to move, to function and to think. Everything needs a power source to run. A computer needs electricity, an engine needs fuel, and humans run off something called ATP (adenosine triphosphate) or more accurately the ‘breakdown’ of the ATP causing energy to be released.

Where does ATP come from?


Let’s start with the most obvious. Why do we eat? We eat because our body needs it to survive. Our food contains vital nutrients that we need to stay living. Our body needs these nutrients to grow, heal, renew itself and produce energy. So essentially ATP comes from the food we eat. 
I would like to make a point here that hopefully you will come to realise the importance and value of good nutrition. It’s our everything, and making sure you maintain a well balanced nutritional diet will mean that your body has the building blocks it needs to keep running smoothly!


When we eat, our digestive system manually and chemically breaks down our food into manageable molecular components that it can use. Carbohydrates get broken down into to glucose, fats into lipids/fatty acids and protein into amino acids. These are the building blocks that I mention above.
With these elements our cells (our body is made up of of billions to possibly trillions of cells) can grow, duplicate, repair and undergo cellular respiration (make and use ATP). Which when you put it altogether is basically ‘living’. A healthy, balanced metabolism will help us to maintain and increase our energy production.

How do we make ATP? – The science bit

Our body is ultra efficient and it has several ways of making energy.


Glycolysis breaks down glucose into pyruvate. This happens as soon as a glucose (sugar) molecule finds its way into one of our cells. With this breakdown, ATP and NADH (a coenzyme) is made. Oxygen is needed for this to happen.

Anaerobic Glycolysis

If there is no oxygen available we can undergo glycolysis without oxygen. This happens in our muscles. When this happens lactic acid is also formed.

Krebs cycle

In our cells we have an amazing organelle called the mitochondria. These little guys fascinate me and I remember when I starting studying anatomy and physiology I fell in love with them! They are like the power stations of our cells. It carries on after the process of glycolysis is finished, like a tag race. 

The Pyruvate and NADH enter the mitochondria and undergo a series of highly complex chemical reactions (Krebs Cycle) to make a very high yield of ATP. The term Krebs Cycle might ring a bell with some of you from studying science in school.

Some of the mitochondria’s other roles include: steroid hormone synthesis, lipid metabolism, insulin/glucose regulation, and cellular calcium homeostasis

And so our cells have all the ATP they need to live!

Nutrition for our Mitochondria

Let’s explore a deeper level to our nutrition. We need nutrients to provide the
essential components for the mitochondria to make energy, to regulate our insulin and glucose levels (blood sugar levels effects our energy too) and more. But what does the mitochondria need to function? Among many other elements I would like to point out three.

  • Vitamin B
    Many of the B vitamins is involved in the process of energy conversion (respiration) in our cells
  • Vitamin D
    Research has suggested that Vitamin D plays an important role in the efficiency of our mitochondria. Vitamin D is also essential for calcium absorption. Calcium is also essential for our Mitochondria.
  • Calcium
    Calcium is a key regulator of mitochondrial function and acts at several levels within the organelle to stimulate ATP synthesis

So at this basic molecular level, when we talk about energy and the miracle that is energy conversion, it becomes apparent (hopefully) that making sure your body has access to all the nutrients, vitamins and minerals it needs will ensure that your body is able to produce loads of energy.

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Myrthe WielerMyrthe has been a massage therapist for almost two decades. Staying informed with new knowledge about movement anatomy and how it integrates with the different systems of the body and mind remains a passion. Myrthe is an ITEC qualified holistic therapist and an ITEC qualified lecturer in Anatomy and Physiology and massage therapy.