Should be sprinters bodybuilding

Muscle fiber types: are you a sprinter or a long distance runner?

Sprinters or long-distance runners, power packs or triathletes - it's all a question of the muscle fiber types with which every person is individually equipped. Find out more about the different muscle fibers and what you can achieve through targeted training.

What are muscle fibers?

The human body is made up of more than 650 muscles: The smooth musculature ensures that our organs are at work for us every day. It works in the background, so we cannot control it. It is different with the striated muscles, also Skeletal muscles called. We can consciously tense and relax you for every movement - regardless of whether you are grabbing cutlery, changing your sleeping position or exercising.

The heart muscle also belongs to the striated muscles, but is controlled separately and outside of our sphere of influence.

The skeletal muscles consist of individual muscle strands that are enclosed by fascia tissue. These strands, in turn, are made up of a bundle of muscle fibers.

The The building blocks of muscle fibers are proteinsthat form so-called filaments. These are structures of different volumes that move when the muscles are active. For example, if you tense your biceps, the filaments slide into one another in such a way that the muscle fibers become shorter. These muscle contractions allow you to move your body, lift weights, or run a marathon.

Once again you have it in black and white: proteins are the building materials of your muscle fibers. It is not without reason that you should rely on a protein-rich diet, especially as a strength athlete. You get support, for example, with our whey protein in many delicious flavors - for strong muscle fibers and consequently more power during training.

What types of muscle fibers are there?

Basically, there are two or three types of muscle fibers:

  1. Muscle fiber type 1 (Slow Twitch or ST fibers, twitching slowly)
  2. Muscle fiber type 2 (Fast Twicht or FT fibers, twitching quickly), which turn into Type 2a and type 2b can be subdivided

How do the muscle fiber types differ?

Let's take a closer look at the muscle fiber types. They differ in their color, the speed at which they contract, their volume, and the number of their mitochondria. These are the “power plants” of the muscle cells, in which fat and glucose are converted into energy, more precisely into ATP.

According to their type, the muscle fibers fulfill different functions. You can imagine that you have different demands on your muscles when you sprint than you do in a marathon.

The muscle fiber types at a glance:

Muscle fiber type 1Muscle fiber type 2aMuscle fiber type 2b
fatigueVery slowlySlowlyFast
Speed ​​of contractionSlowlyFastExplosive
Energy supplyAerobic (with oxygen)Aerobic (with oxygen)Anaerobic (without oxygen)
Main energy storageFatsCarbohydrates, creatineATP, creatine
Loading timeMore than 30 minutesLess than 30 minutesLess than 60 seconds
sportsEndurance sports over long distances (e.g. marathon)Endurance sports over medium distances, strength endurance training (e.g. climbing and swimming)Sprinting, weight training, weight lifting


As soon as you activate a muscle, the body tries to work as efficiently as possible. First of all, it controls the type 1 fibers, which are slower and consequently use the least amount of energy. The type 2 muscle fibers are only switched on when the effort really requires it.

For example, if you go from A to B, your type 1 muscle fibers will suffice. For a squat, on the other hand, you need significantly more strength. Your body activates the type 2a muscle fibers and finally the muscle fiber types 2b to handle the load.

What type of muscle fiber are you?

Just like you, your muscles are also unique. Every muscle in your body has proportions of all three types of muscle fibers. However, the distribution or number is completely individual and depends on two factors: muscle function and genetics.

Your back muscles, for example, have the main function of straightening and stabilizing the body. It does not have to work explosively and quickly, but withstand loads over a long period of time. The back muscles are naturally equipped with more type 1 muscle fibers.

In addition, the distribution of muscle fiber types is genetically determined. So whether you have more endurance or, above all, powerful muscles and whether you prefer endurance runs rather than sprints is a predisposition.

Exercise muscle fiber types

The distribution of muscle fiber types - fast and powerful vs. slow and persistent - is something you were born with. You're more of an endurance or strength type by nature. Is it then even possible to turn a born bodybuilder into a marathon runner and vice versa?

A muscle fiber type 1 will always remain type 1. You can't screw it up, no matter how much time you spend in the gym. With an appropriate training you can make your muscle fiber types more efficientso that the proportions within the muscle cords change. The more area muscle fiber type 1 or 2 takes up, the greater your endurance or your maximum and speed strength.

So basically everything is a question of training and your own motivation. Anyone who wants to run a marathon and works hard for it will make it - no matter how your muscle fibers are made up. Whether you enjoy doing it and how successful you are is of course a different matter.


  • Muscles are made up of different types of muscle fibers: muscle fiber type 1 is persistent and slow-twitching, muscle fiber type 2 is powerful and fast-twitching.
  • Muscle fiber types 1 are active in endurance sports with exercise times of more than 30 minutes, for example in a marathon.
  • In strength training or sprints, when fast, explosive and powerful movements are required, type 2 muscle fibers come into play.
  • The distribution of the muscle fiber types is individual and depends on the respective function of the muscle and on the genetic requirements.
  • The number of muscle fiber types is innate, but they can be made more efficient through appropriate training.
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