Cardiorespiratory endurance measures how long you can exercise at your target heart rate before tiring out, which is determined by how many slow-twitch muscle fibers you contain in your body.
Sprinting or long-distance running, which do you prefer? Can you excel in both? Many individuals think that the proportion of fast-twitch vs. slow-twitch muscle fibers determines the sports in which players thrive and how they respond to training.
Muscle Fiber Types
Myocytes comprise the bundles of individual muscle fibers that compose skeletal muscle. Each myocyte has many myofibrils, which are protein filaments (actin and myosin) that may grip and pull each other. This causes the muscle to contract by shortening it.
It is commonly acknowledged that muscle fibers may be divided into two major categories: slow-twitch (type I) and fast-twitch (type II) fibers.
These distinctions appear to affect how muscles respond to training and physical exercise, and each fiber type has a different capacity to contract in a certain manner. Slow and rapid fiber types are genetically determined in human muscle tissue.
Most of the muscles utilized for movement have around 50 percent slow-twitch and 50 percent fast-twitch fibers.
Slow-Twitch Muscle Fibers (Type I)
Slow-twitch muscle fibers are more effective in utilizing oxygen to produce more adenosine triphosphate (ATP) fuel for prolonged, continuous muscular contractions. They fire more slowly than fast-twitch fibers and are resistant to fatigue for an extended period.
As a result, slow-twitch fibers are excellent for enabling athletes run marathons and bike for hours.
Fast-Twitch Muscle Fibers (Type II)
Because fast-twitch fibers utilize anaerobic metabolism to manufacture fuel, they are superior to sluggish muscles at producing brief bursts of strength or speed.
However, they tire out more rapidly. Fast-twitch fibers produce the same force per contraction as slow muscles, but they can contract more rapidly, hence their name.
Having more fast-twitch muscle fibers is advantageous for sprinters because it allows them to create force rapidly.
These muscle fibers also go by the name intermediate fast-twitch fibers. They can generate energy using both aerobic and anaerobic metabolism nearly equally. Thus, they are composed of type I and type II muscle fibers.
These “traditional” fast-twitch muscle fibers utilize anaerobic metabolism to generate energy and excel at generating rapid, strong bursts of speed. This kind of muscle fiber has the fastest contraction (rapid firing) rate of all the muscle fiber types, but it also has a higher rate of exhaustion and cannot endure for as long before it requires rest.
Does The Type Of Muscle Fiber Affect Athletic Performance?
Your muscle fiber type may impact the sports in which you excel naturally and your speed and strength. Typically, Olympic competitors choose activities that reflect their genetic composition. It has been determined that Olympic sprinters have around 80 percent fast-twitch fibers, but marathon runners often have 80 percent slow-twitch fibers.
Fiber type contributes to an athlete’s success, although it is a poor predictor of performance. In addition to mental readiness, good nutrition and hydration, adequate rest, and having the necessary equipment and training, other aspects contribute to athleticism.
Can Training Change The Kind Of Muscle Fibers?
Some data suggest that training may cause human skeletal muscle fiber types to change from “quick” to “slow.” This is not fully understood, and researchers are still investigating the issue.
Keep in mind that genetic disparities at the highest levels of physical competition may be significant. However, according to the scientific principles of conditioning can significantly enhance the performance of the average athlete. With repeated endurance training, muscle fibers can grow and become better able to withstand and adapt to exercise stress.
View Also –