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Why Do Runners Lose Muscle and How to Prevent It

I have just come back from a run and wondered why runners lose muscle mass. I did some research on why and how to prevent it.

When muscle fibbers don't have enough time or nutrients to repair, or if the muscle is under constant stress, it can lead to muscle loss instead of muscle growth. This can result in a loss of muscle mass and strength. To prevent muscle loss while running, it is important to ensure proper nutrition and eat enough protein. You should prioritise rest and recovery into your training schedule and consider adding weight training to your routine to maintain muscle mass and improve overall fitness.




If you are a runner, you may have experienced a loss of muscle mass at some point and wondered why. Losing muscle can negatively impact your running performance. Let’s take a look why this happens and how to prevent it.

What is Muscle Loss and How Does It Affect Runners?


Muscle loss, also known as muscle wasting or muscle atrophy, is a condition in which the muscle tissue decreases in size and strength. For runners, muscle loss can significantly impact their running performance, as muscles play a vital role in running. Muscles help provide energy and endurance. Without enough muscle mass, runners may experience a decrease in speed, strength, and stamina.

Why do Runners Lose Muscle?


Running is a high-intensity exercise that places a significant demand on the muscles. When we run, our muscles contract repeatedly, which can cause microscopic tears in the muscle fibbers. These tears are a natural part of the muscle-building process, as the body repairs the tears by building new muscle tissue, resulting in muscle growth and strength.


This means running actually increases muscle mass. So why do some runners lose muscle?


When the muscle fibbers don't have enough time or nutrients to repair, or if the muscle is under constant stress, it can lead to muscle breakdown instead of muscle growth. This can result in a loss of muscle mass and strength.

Does Running Burn Muscle?


To further answer this question, when you go on a run your body will start to burn through stored carbohydrates and after about 30 to 60 minuets you will start to burn fat.


The muscles will not be broken down unless there is not enough energy to be used in the form of carbohydrates (glycogen) or fat.

Factors contributing to muscle loss in runners


Several factors can contribute to muscle loss in runners. Understanding these factors can help you take steps to prevent muscle loss and maintain your muscle mass.

Overtraining


Overtraining is a common cause of muscle loss in runners. When you push your body too hard, your muscles don't have enough time to recover, leading to muscle breakdown. Additionally, overtraining can cause an increase in cortisol levels, a stress hormone that can also contribute to muscle loss.

Lack of protein intake


Protein is essential for building and repairing muscles, a lack of protein intake can lead to muscle loss. As a runner, you need to make sure you are eating enough protein to support muscle growth and repair.

Aging


As we age, our bodies naturally lose muscle mass. This can begin as early as our 30s and can lead to a loss of strength and endurance.

Injury and inactivity


When we are injured or inactive, our muscles aren't being used, leading to muscle breakdown. This can result in a loss of muscle mass and strength.

Genetics


Genetics can also play a role in muscle loss. Some people may lose muscle mass more quickly than others.

How to prevent muscle loss while running


Now that we have discussed the factors that contribute to muscle loss in runners, let's talk about how to prevent it. Here are some tips to help you maintain your muscle mass while running.

Proper nutrition


Proper nutrition is in my opinion the most important factor for maintaining muscle mass. As a runner, you need to ensure that you are eating enough calories and nutrients to support your training. Make sure to include plenty of protein in your diet to support muscle growth and repair.

Rest and recovery


Rest and recovery are just as important as training when it comes to preventing muscle loss. Make sure to give your muscles enough time to recover between runs and add rest days into your training schedule.

Resistance training


Resistance training, such as weightlifting, is a great way to build and maintain muscle mass. Including resistance training into your routine can help prevent muscle loss and improve your running performance.

Incorporating cross-training


Adding cross-training to your routine such as cycling or swimming, can help prevent muscle loss while providing a break from the repetitive motion of running. Cross-training can also improve your overall fitness and help prevent injury.

Conclusion


Muscle loss can negatively impact your running performance. By understanding the factors that contribute to muscle loss and taking steps to prevent it, you can maintain your muscle mass and improve your running performance.

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