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Jason Kelly

The Importance of Slow-Twitch Muscle Fibers for Martial Artists

martial artist

Visualize, the fight begins. You go into your defensive stance. You spend about 30 seconds moving around looking for an entry point or angle to punch, kick, or lock up and take down your opponent. You find the point and throw an explosive punch. Your opponent blocks it. You go back into your defensive stance and wait to find another opportunity. Or, let's say in jiu-jitsu, you spend 2 minutes in the mount or guard position waiting to find the opportunity to execute the right technique with speed and explosiveness.


Punch faster, kick quicker, throw harder. Yes, these are all important to develop in your martial arts. However, martial arts and jiu-jitsu are not predominantly explosive sports. They are sports that use explosive techniques that have bursts of speed from their aerobic base. And, if your aerobic base has no strength, no foundation, then it affects your endurance, explosiveness, and speed. After you perform an explosive fast technique like a kick or throw without success, where do you have to return, to your aerobic base.



Let's understand the three different energy systems so you can comprehend their integration into martial arts.



Slow-Twitch Fibers


slow twitch fibres

The misconception about slow-twitch fibers is that they are weak. They are not weak. They just produce less force than the other two systems. You can and need to strengthen your slow-twitch fibers. Slow-twitch fibers are necessary to develop in your training to optimize your strength, speed, and power.


Slow-twitch muscle fibers are important for all athletes. These fibers stabilize your joints, alignment, posture, and help prevent injury. If your slow-twitch fibers are not strong, your alignment and joints will be weak. When using fast-twitch fibers, moving through large ranges of motion, or using bigger muscles, they create high amounts of force. If your slow-twitch fibers are not strong enough to support and stabilize your alignment and joints, when generating high amounts of force, you will be more prone to injury. Alignment and stability are similar to the foundation of a building. Is the foundation concrete or sand? Which one can withstand greater force over a longer time? This is similar to your slow-twitch fibers and how they support force.



Firstly, the key for training slow-twitch muscles are high repetitions and low resistance. This will increase the strength of the slow-twitch fibers. Secondly, training aerobically greater than 3 minutes or more creates more mitochondria to increase endurance capacity. Mitochondria are cells that boost endurance. The more you have, the greater your endurance.


Think of slow-twitch fibers as sustainability. If you can run 3 minutes at 9MPH. And, from training over time, you can run 3 minutes at 8MPH. You have increased your mitochondria and endurance. If you can do 15 reps with 50 lbs. And, over time from training, you can do 15 reps with 65 lbs. Well, now you increase slow-twitch muscle strength. Again, it is not that they are weak they just produce an overall strength base.


In order to tap the slow-twitch fibers, the aerobic activity needs to be sustained for 3 minutes or longer. Slow-twitch fibers should be trained first before fast-twitch fibers. Your alignment and joints need strength to stabilize first, to sustain force, before generating it.



Fast Twitch Fibers


human body muscle structure

Fast-twitch fibers are large fibers that produce high and quick force.


Type IIA fibers are a mixture of slow and fast-twitch fibers. They are highly oxidative like slow-twitch fibers that are resistant to fatigue and also are glycolytic to generate higher amounts of force during anaerobic training. These muscle fibers can use both oxygen and glucose. They are hybrids and switch back and forth depending on the activity you are doing. Their duration is from 10 seconds to 3 minutes.


Type IIB fibers are fast-twitch. They are low oxidative and highly glycolytic that fatigue rapidly. These fibers are quicker to fatigue because they are glycolytic and have little to no mitochondria. They do not use oxygen. Type IIB fibers produce the greatest amount of force but only up to about 10 seconds in duration.



Now again visualize, the fight begins. You go into your defensive stance. You spend about 30 seconds moving around looking for an entry point or angle to punch, kick, or lock up and take down your opponent. You find the point and throw an explosive punch. Your opponent blocks it. You go back into your defensive stance and wait to find another opportunity. Or, in jiu-jitsu, you spend 2 minutes in the mount or guard position waiting to find the opportunity to execute the right technique with explosiveness and speed. Slow-twitch fiber sustainability provides the necessary strength and time for the faster exhaustive muscles to recover and be used again during the match.


Now that you understand each system, you can improve and enhance your martial arts training accordingly. Don't underestimate slow-twitch fibers. Again, they are not weak, they are about sustaining rather than generating. They need to be strong. All the systems function together like an orchestra playing a symphony, the low tones support the high ones. Take out the low tones and the high ones lose support and don't sound so good.




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