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Fitness Tips

What’s the Difference Between Fast-Twitch and Slow-Twitch Muscles Fiber?

If you spend any time scanning fitness magazines or eavesdropping on powerlifters, then you know that there are two primary types of muscle fibers.

Fast-twitch and slow-twitch muscle fibers perform different functions for movement. Understanding how and when each muscle fiber works is essential because, without that knowledge, you won’t know how to train them.

Whether you’re new to our gym in Las Vegas or looking to take things to the next level, you need to know these basic facts about the different muscle fibers.

What Are Slow-Twitch Muscle Fibers?

Slow-twitch muscle fibers (type 1 muscle fibers) are the fibers that activate during aerobic activity. They’re the first muscles to contract, and they light up during your warm-up and continuously if you are participating in endurance exercise.

These fibers propel you forward during extended, slow exercise programs, like rowing, running, or biking. They use oxygen efficiently to provide fuel for the extended contracts you need to move over a long period. To get there, they rely on a massive number of capillaries to bring them a sustainable supply of oxygenated blood.

Although slow-twitch fibers carry on for extended periods, they can’t generate the force you need to sprint. If your slow-twitch tissues can’t help you out, your fast-twitch tissues turn on.

What Are Fast-Twitch Muscle Fibers?

Your fast-twitch muscle fibers include two groups: moderate fast-twitch and fast-twitch. The first of these to contract is the moderate fast-twitch muscles, which are thicker and right off the starting block when your slow-twitch muscles can’t provide the intensity.

If you need a real burst of speed, your fast-twitch muscles kick in. But you can’t rely on them very long because they only activate as you reach a level of maximum exertion.

Why Does It Matter?

Understanding how your muscles fibers work together to propel you from the starting line to the finish is essential. The two fibers are physically different, which means you need to train them differently.

For example, training slow-twitch fibers occurs when you keep the fibers contracted for extended periods using sustained isometric contractions. The single-leg balance or the front plank help you build those muscles. As you hold the contractions, you teach the muscles to use oxygen more efficiently, which produces more energy.

Other helpful slow-twitch training techniques include resistance training with slow tempos and low weights, circuit training with short intervals and light weights, and body-weight exercises.

To train your fast-twitch muscle fibers, you need to use heavy weights. The difficulty of the move lets your body know it’s time to activate all the available muscle fibers. Explosive and power-based movements using a small number of repetitions are the way to go.

However, you have to keep in mind that fast-twitch muscles run out of energy quickly, so you need to keep your rep count low and your rest period high.

If you only train one type of muscle fiber and not the other, you’ll start to see weaknesses appear, particularly if you have specific goals for your workouts.

One Muscle Fiber is not Like the Other

Whether you go for a run or pick-up a barbell, you’re not just working random muscles. A chain reaction that starts with slow-twitch and works its way up to fast-twitch muscle fibers is occurring. Strengthening both types of muscle fiber helps your body move better.

Are you looking for a gym that will help you reach your fitness goals? Get in touch to learn more about how our unique training programs make us the best gym in Las Vegas.