How Do You Twitch?!

By: Karyssa Shaw

One Twitch, Two Twitch, Red Twitch, Blue Twitch

Most people know athlete types as “strength” athletes and “endurance” athletes. Strength athletes are your powerlifters, wrestlers, sprinters and football players. The movements necessary for these sports are quick and powerful. Endurance athletes are your marathon runners, swimmers, soccer players, and cyclists. These athletes need to be able to work for a long period of time without tiring. Scientifically, these athletes are categorized by their muscle fiber type. Strength athletes have “fast-twitch” muscle fibers. This means the muscle fibers contract quickly but tire rapidly which is why they are good for sports with explosive movements. Endurance athletes have “slow-twitch” muscle fibers which means they contract slower but are able to work for longer periods of time without tiring. Likewise, any type of long distance athlete is going to have slow-twitch muscle fibers. 

Slow-twitch muscle fibers are fatigue resistant, and focused on sustained, smaller movements and postural control. They are aerobic in nature unlike fast-twitch fibers which are anaerobic. Slow-twitch fibers are also sometimes called “type I” or “red fibers” because of their blood supply. Fast-twitch muscle fibers provide bigger and more powerful forces. Since fast-twitch muscle fibers are anaerobic, they have less blood supply, hence why they are sometimes referred to as “white fibers” or “type II”. Skeletal muscles, in every living being regardless of activity level, contain both types of fibers, but the ratios can differ depending on a variety of factors including muscle function, age and training. Non-athletic individuals have an almost balanced ratio of fiber types. 

I have always been a strength athlete. Growing up, I was a cheerleader and gymnast in the Fall and Winter, but spent the Spring and Summer months on the softball field. Even to this day, I am still playing softball. As I got older, I spent a lot of my time in the gym and I even joined a CrossFit gym when I was in college. To be quite honest, the only time I considered myself both a strength and endurance athlete is when I did CrossFit. I had the perfect mix of fast-twitch and slow-twitch muscle fibers. But since stopping CrossFit almost 3 years ago and just focusing most of my time on strength training and not as much cardio based training, I guess I just tried to embody the characteristics of a “fast-twitch” athlete. 

I started competing in Olympic Lifting when I was a CrossFit athlete. I completely fell in love with the the heavy weights, explosive lifts, and the feeling I got when I would PR (set a new personal record). Not every lift went as expected but it would give me the drive to push harder and lift heavier. With these types of lifts, it was essential that my body recruited those fast-twitch muscles fibers we talked about. Deep breath in, brace your core, and lift!

Everyone has their niche, but regardless of what type of athlete you are, strength or endurance, it is still important to train both types of muscle fibers. Think about it, those giant football players you see on TV every Sunday, don’t just “lift things up and put them down”. They also hop on the bike every once in a while 😉