When was the last time you fell or nearly fell? Did you catch your foot on a curb or step? Do you have a spring in your feet or do your feet move like Frankenstein? When was the last time you danced?
If you find you are dragging your feet a bit more or tripping, maybe it’s because your fast twitch muscles are letting you down.
What is a fast-twitch or slow-twitch muscle?
Fast-twitch and slow-twitch muscles are two types of muscle fibers, each having unique properties that affect how the muscle responds to physical activity.
Fast-twitch muscle fibers, or type II fibers, produce rapid, forceful contractions. Think of something that happens quickly, like tripping AND catching yourself before you fall versus falling flat on your face. That is your fast-twitch muscles at work. The ability to have a quick motion and a quick stop.
Fast-twitch fibers tend to tire quickly. Think of a sprinter running a short distance very quickly versus a person running a marathon, which is much longer and not going as fast as a sprinter (the elite marathoners are faster than blazes in my book, but they are still using slow-twitch muscles).
I really enjoy incorporating exercises in my class like fast foot movements and quick lateral movements. I see many in the class struggling with moving their feet, but the goal is to keep moving and working on that speed. Doing fast footwork with a sudden stop or deceleration activates the fast-twitch muscles.
Some activities that utilize fast-twitch muscles include:
- strength training (heavier weights with fewer reps)
- agility training
- high-intensity interval training (HIIT)
Two stories about a fall and a near fall
Compare these two stories:
I was walking with a walking group and chatting with a woman who was probably in her late 70s. As we were talking, she caught her toe on a one-way spike at the entrance of a parking lot. Boom! Faceplant, bloody face, and an injured wrist. No broken bones – a close call and wounded pride.
I was out running last year after a rain storm. I was running along the roadside facing oncoming traffic and hit a long stretch of mud. I went sliding forward (seemingly forever) and almost slid into traffic but caught myself before falling and getting injured. I’m almost 69 yrs old.
Yes, it is about a 10-year gap in age between Story A and Story B, but it’s important.
Strong activated fast twitch muscles kept me from falling, but weaker fast twitch muscles did not keep my walking partner from a fall.
Slow-twitch muscle fibers, or type I fibers, are designed for sustained, low-intensity activity. They are more resistant to fatigue. Think long-distance running, cycling, and swimming. Slow-twitch fibers more efficiently use oxygen to produce energy, resulting in a muscle that is less likely to tire.
Aging and our muscles
As we age, our muscle fibers naturally begin to shrink and weaken, leading to a decline in physical performance. This process known as sarcopenia affects both fast-twitch and slow-twitch fibers. However, slow-twitch fibers tend to decline slower with age than fast-twitch fibers.
To slow the effects of aging on muscle fibers, it is important to engage in regular physical activity that challenges both types of fibers.
Types of activities you can do
Many activities, such as boxing and basketball, incorporate both slow-twitch and fast-twitch fibers.
The chest muscles, triceps/biceps, and hamstrings are more fast-twitch. Shoulders, forearms, and calves are more slow-twitch. Quads and back muscles tend to be a mix.
The biggest muscle in your body, your glutes are 50% fast twitch and 50% slow twitch muscle fibers. So work it, baby!
I don’t expect you to be a sprinter, but you do need to do resistance/strength training. Try moving quickly and then STOP suddenly. The last thing you want to do is to fall and break your hip. A little cha-cha can go a long way.