Types of Muscle Fibers
Muscle Fiber and Its Types
Athletes need to know the muscle fiber and its types as it helps them to analyze their body as well as performance in a better way. There are three types of muscle fibers which are present in the human body and each has its own specific features and functions. Various training programmes are conducted in order to educate the athletes of the same.
The human body is made up of a number of muscle fibers which helps the individual to perform various activities and also provide energy. Various training programmes are conducted for the athletes to understand the muscle types and how it enhances their performance.
The skeletal muscles are basically divided into two types- red muscle fibers and white muscle fibers depending upon their colour. The red muscle fiber contains high level of myoglobin, they also contain oxygen storing proteins in them. Thus they are red in colour and hence the name. On the other hand, white muscle fibers have a white appearance. They have less amount of mitochondria and blood vessels than the red.
But there is yet another basis on which muscles are based- depending upon their twitch capabilities. Thus they are fast twitch muscle fibers and slow twitch muscle fibers.
The fast twitch muscle fibers are further divided into Type A Fast Twitch Muscle Fibers and Type B Fast Twitch Muscle Fibers.
Type A Fast Twitch Muscle Fibers
They are known to generate the most forceful contradictions amongst all the muscle fibers. They are known to be quite rich in motor neurons but low in mitochondrial density. These fibers are however not able to make the best use of oxygen available to them. Type A does not make use of the stored body fat rather it relies on the stored glucose. They have a medium capillary density.
Type B Fast Twitch Muscle Fibers
They are best suited for short duration exercises, rather than the long ones for which Type A is better suited. They also have a good quantity of mitochondrial density along with resistance to fatigue also. These muscles make a good use of oxygen available to them owing to the contraction abilities of these muscles. They are said to be very sensitive to fatigue.
Slow Twitch Muscle Fibers
This is the muscle fiber which is made use of during marathon running or any other extra long run. Apart from having a high oxidative capacity the best thing is that they are able to resist fatigue for over a longer period of time and hence they are made use of when in the marathon running. But they are very slow to contract and so may not work well in high enduring exercises. They are rich in mitochondrial activities as well as capillaries. They also have a high myoglobin content but low in glucogen content.