NASM Chapter 4 continued.

ATP is important.

How important?

Really Important. It’s explosive energy that our bodies know how to use.

How do we use it?

By breaking one of the bonds of the phosphate

Then it becomes
Resulting in a Phosphorus Atom flowing around.

The double bonded phosphorous and Adenine, become something called

Adenosine Diphosphate. Still pretty cool, but not as powerful as the Adenosine Triphosphate.

But you got that Phosphate floating around, why don’t you just reattach it?

You are a genius! That is the solution!

But remember

The Law of Conservation of Energy..

Which bring us to the first and quickest form of ATP replenishment.

The ATP-PC system.

The goal of this is to attach a Phosphate from the Phosphocreatine (CP, or PC)to the depleted Adenosine Diphosphate, to recreate Adenosine Triphosphate ATP.

It goes on and on, till you die. Well not really.

So this is fast. Powerful. BLAMO! think high intensity, short duration, sufficiently supplied with oxygen. This ATP-PC system can provide energy for 10 to 15 seconds, before complete exhaustion. Because the ATP and PC stores are depleted.

So what happens when the ATP stores during the ATC-PC system are depleted? Do we die?

Calm down. Your body has fail safes. Let’s talk about them now.

The second ATP harnessing method that is a little longer (30–50 seconds)

is something called Glycolysis. Before you can use glucose it must be converted into a compound called Glucose 6 Phosphate. But back to that law of conservation of energy. There are not free lunches. The energy just doesn’t materialize out of thin air. Glycolysis does not begin until either glucose or glycogen are converted into Glucose 6 Phosphate. But to get Glycolysis going you have to use one ATP molecule to convert Glucose. However if you have Glycogen no ATP is required. Thusly the end result of Glycolysis broken down into different types of acids. Pyruvic Acid (Aerobic Glycolysis) and Lactic Acid (Anaerobic Glycolysis). Remember two ATP for each mole or unit of Glucose. While Glycogen creates 3 ATP.

Thus this ATP system burns out around 30–50 seconds or 8 to 12 repetitions.

Lastly and the most important system of ATP utilization is Oxidative System.

There are 3 steps of Oxidative System. These are all aerobic (With Oxygen)

  1. Aerobic Glycolysis.
  2. Krebs Cycle.
  3. Electron Transport Chain.

It is the same as regular Glycolysis but with the presence of oxygen the Pyruvic Acid is converted into an important metabolism molecule called Acetyl Coenzyme A (Acetyl CoA).

What Acetyl Coenzyme A does is it contributes Substrates to the second process of oxidative production of ATP called the Krebs cycle.

The complete oxidation of acetyl CoA produces two units of ATP and the by products are carbon dioxide (CO2) and Hydrogen (H).

Hydrogen ions released during the glycolysis and during the Krebs cycle combine with other enzymes and in the third process of oxidation, ultimately provide energy for the oxidative phosphorylation of ADP to ATP. Otherwise known as the Electron Transport Chain.

Whoa….Depending on certain factors in the oxidative system metabolism of a single molecule produces 34 to 40 ATP.

What we just discussed was the utilization of carbohydrates as a fuel source. Fats can be metabolized aerobically as well. So fats come in as Triglycerides then they are broken down into smaller sub units called (FFA) or Free Fatty Acids.

This is a process called B -oxidation. B- oxidation takes those FFA and turns them into Actyl-CoA. Which can then enter the KREBS cycle.

Remember Carbohydrates are quick and dirty, and need less oxygen to produce ATP.

Fats although can produces more ATP, require more oxygen.

So the aerobic metabolism of carbohydrates and fats yields water and carbon dioxide.

You know what’s crazy? Google Photosynthesis reaction, you will see alot of the same things, but different.


It’s great.

We need it.

We get it through

  1. ATP-PC system (10–15 seconds)
  2. Glycolytic System Aerobic, or Anaerobic (16–50 seconds)
  3. Oxidative System (indefinite) Because every cell in your body has a layer of fat. Which if necessary could be used for energy.

When you are crushing the gym think about what we talked about during your exercises.

And Remember Live Creatively

See Things in New Perspectives

Work Passionately

If I messed up, or didn’t clarify something. let me know in the comments. Conversely if I did a good job. I would appreciate some love.

Thank you!

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