How Muscles Produce Energy – What You Need To Know

How do Muscles Produce Energy?

This question might not be as common as “how can i gain muscle fast?”, “What is the best budget protein powder?” or “What gear are you on” among gym rats. However it is still an interesting topic.

In order to get our muscles to grow, our bodies need energy to carry out intense workouts. A high protein diet is required to help them repair and grow back stronger. One of the most common supplements that many of the athletes i’ve interviewed use are protein powders. However protein intake is concerned with the repair of muscle tissue to make it grow bigger and stronger.

In order to carry out any kind of physical activity, our bodies need energy. During intense workouts, our muscles need this energy on tap.

Without it, workouts won’t be as effective, and gains won’t be optimal.

Scott Edmed is here today, explaining how muscle product energy.

Take it away Scott!

How Muscles Produce Energy

Let’s start with Adenosine Tri-Phosphate (ATP), the immediately usable form of chemical energy for all human work. It is stored in all cells in small amounts and is used up quickly during training and exercises.

When ATP is used for energy, it loses a phosphate molecule and becomes Adenosine Di-Phosphate (ADP) releasing energy. To keep fueling activity, ADP must then be restored back to ATP with an additional phosphate.

There are three pathways for rebuilding ATP from ADP, and the one employed depends on both the intensity and duration of the physical activity.

First Pathway

The first pathway involves breaking down phosphocreatine to obtain phosphate for ATP production. But phosphocreatine is also limited in supply (this is why many athletes supplement with creatine hoping to maximise phosphocreatine levels) restricting the usefulness of the ATP-phosphocreatine system to very short duration activities, such as a 10 second sprint or a heavy triple on the bench press.

Second Pathway

A second pathway utilises anaerobic respiration and glycolysis, the first step of respiration, which kicks in after phosphocreatine can no longer supply the needed energy. The body falls back on this less efficient method of producing ATP under low oxygen conditions.

In the absence of oxygen, carbohydrates (from glycogen and blood glucose) are used as the fuel source and are converted to pyruvate producing two molecules of ATP. This first step of respiration, is limited by the buildup of excess acid in the cell when oxygen levels are limited.

The ‘burn’ sensation you feel in your thighs as you run up a hill or perform a twelve-rep set of squats is caused by lactic acid build-up.

Third Pathway

The third pathway is the aerobic system, which predominates in low-intensity, longer-duration activities such as walking and jogging, when oxygen is available. The aerobic system is also the energy system most active at rest.

During these activities, enough oxygen can be supplied to the cells via the lungs and bloodstream.This allows for glucose to be broken down completely, through glycolysis, the Krebs cycle and then onto the Electron Transport Chain, producing ATP, hence avoiding the build-up of lactic acid.

The Role of Glucose

Therefore glucose and stored glucose in the form of glycogen, is the most rapidly accessible energy source in the body, and the most important source for muscular contraction, but what if the body runs out of glucose?

The aerobic system can utilise energy production from fat during low intensity exercise, especially when one becomes fitter, however, at high intensity levels of exercise fatty acids cannot be utilised quickly enough to supply energy and the production of ATP.

Lipases are released into the bloodstream and break down fats in the bloodstream. The fatty acid tails can then enter the Krebs cycle allowing respiration to continue.

When glucose and fat stores are unavailable, amino acids can provide energy. Protein enzymes will break proteins back down to amino acids and then once the toxic ammonia group is removed the remainder of the amino acid can be rearranged to enter aerobic respiration at different stages.

Many intra & post workout shakes have a combination of bcaa and fast acting carbs. Examples of these shakes are Hurricane XS from Myprotein or Maximuscle Cyclone.

Over To You

Hopefully you have a more grounded understanding of the role of ATP, energy, and how supplements can enhance performance during intense workouts and in the gym. It’s crucial that diet is in check, however i also use creatine and BCAA as part of my protein supplement stack.

You may want to consider adding these to your supplement stack to maximise the results you’re seeing from each of your workouts. You can check out what supplements fitness models such as Sergi Constance & Simeon Panda use by clicking those links.

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