We’ve all been there. Wanting to increase our max speed on the treadmill, up the number on our weights, use more power than our previous workouts. We think that using more power, speed, weight = more effective, when really activating our hard-to-reach smaller muscles is equally as important. You know, that shaky feeling you get when you hold plank? Today we’re looking at the difference between fast & slow-twitch muscle fibers and how they help keep us feeling long, powerful, and strong on the reg.

What is a Muscle Fiber?

Muscle fibers are skeletal muscles, or muscles that directly connect to the bones in our bodies, allowing us to move our limbs, maintain posture, balance, produce energy, and protect vital organs. These skeletal muscles also store important minerals and fats in our body will producing blood cells to maintain health. All of these muscles move voluntarily. For example, when you lift your arm, your brain is telling the muscles in your arm to move. Skeletal muscles are mostly found in the arms, legs, abdomen, back, and head, hence on the Megaformer we work our arms, obliques, abs, and cheeks. There are two types of skeletal muscle fibers, fast-twitch and slow-twitch, which function differently and have crucial roles in your movement and exercise routine.

1. Fast-Twitch (Type II) Muscle Fibers:

   Fast-twitch muscles are large in size but quicker to tire because the body produces energy without oxygen (anaerobic). They are used for power, force, and quick contractions. Some workouts that optimize your fast-twitch muscles are lifting weights and powerlifting (heavy weight, quick reps); sprinting and agility (speed); and jumping (power). All require force and momentum, but are quick to fatigue. Ever wonder why you feel so out of breath after a sprint? Your fast-twitch muscles are why!

2. Slow-Twitch (Type I) Muscle Fibers:

   Slow-twitch muscles are much smaller than fast-twitch muscles but do not fatigue nearly as fast. They can sustain longer contractions or time under tension. Workouts that activate more of your slow-twitch muscles are the Megaformer, marathon running, swimming, and endurance training. All require the body to produce energy with oxygen (aerobic) over long periods of time to fatigue. Think about holding a plank or a wall sit. You are not immediately out of breath when you first stay in your hold like you would if you just ran up and down a flight of stairs. Instead, the muscles slowly start to burn until they produce a shake.

Embrace the Mega Shake

So what is the Mega Shake? Since the Megaformer workout largely uses slow twitch muscles, we spend a lot of our time under slow, controlled tension which eventually causes our muscles to shake. This shake is what we LIVE for on the Megaformer, because it means although your body is starting to fatigue, it’s also when the biggest changes happen. It’s when your body creates long lean muscles, your flexibility increases giving you more power behind each movement, and you get stronger. Through smooth transitions, Core (LP) is able to help you maximize the results you get from slow-twitch muscle training.

It’s important to remember that as we age, we have a decline in our fast-twitch muscle fibers but an increase in our slow-twitch fibers. In order to avoid as drastic of a loss in lean muscle which can lead to body composition changes, increased risk of falls, etc…that we combat these effects as much as we can with slow-twitch training.

What are your favorite fast & slow twitch exercises?

Resources:

https://blog.nasm.org/fitness/fast-twitch-vs-slow-twitch

https://www.verywellfit.com/fast-and-slow-twitch-muscle-fibers-3120094

https://journals.physiology.org/doi/full/10.1152/japplphysiol.00299.2006