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  • Writer's pictureJulia Kozelka

What is Muscle Hypertrophy?

Muscle Hypertrophy is essentially the increase in size and growth of muscle cells. I like to think of this like a callus. The harder you rub down on your skin, the thicker the callus forms.

There are two main components for muscle hypertrophy, the stimulation and the repair of muscle cells. First, when we lift weights, we are stimulating a contraction in our muscles. This contraction is what causes tiny micro tears in our muscle fibers. As we continue to workout, those muscle fibers continue to break down. This is why progressive overload is so important. If we are not continuously challenging our muscles, we won’t be able to stimulate them for growth. Second, after the workout, those muscle fibers start to get repaired. New muscle fibers begin to grow to replace and repair the damaged ones. Most of the time, more muscle fibers are made than you had before which is why muscle growth occurs. This usually happens the most at night, when your body is at rest. That is why it is so important to get a good nights sleep. It allows you to grow and repair those fibers better and more efficiently.

There are also different kinds of muscle fibers that you can grow. This usually depends on the kind of exercise you do. We have type 1 fibers (slow twitch) and type 2 fibers (fast twitch). Slow twitch muscle fibers are longer and slimmer than fast twitch fibers. They can conserve more oxygen and can give off more energy for longer periods of time. Good examples of someone with more slow twitch fibers would be a marathon runner or bicyclist. That is why they seem to have smaller, leaner looking muscle. Fast twitch muscle fibers are thicker. They contract faster, but for a short period of time and use oxygen quickly. These muscle fibers are more prominent in weightlifters, sprinters, or high impact sports like football players. Thats why they seem to have bigger, thicker muscles. Although we carry both types of fibers, your training will determine which ones you develop more and can change as your type of exercise changes.

Lastly, our genetics play a huge roll in muscle hypertrophy as well. These include the degree of which your muscles grow, the speed of muscle growth and the appearance or shape of your muscles. For some, you may be able to put on muscle very fast, for others, very slow.

In conclusion, muscular hypertrophy occurs when your stimulate your muscles enough to cause damage to the muscle fibers. When the muscle fibers get repaired, new ones are grown. They grow into either slow twitch or fast twitch fibers based off the exercise you do. Your genetics determine the degree, speed and appearance of the muscle grown.

Do you want to know how to accelerate your own muscle growth for better results?

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