Comparing human muscles to those of a hummingbird
One of the pleasures of life is being able to relax and sit outside watching all that goes on around you. One of the favorites is trying to identify the different birds that visit your area. Probably the most fun bird to watch is a hummingbird eating at a hanging feeder in your yard or even hitting on the flowers in the yard. The hummingbird is so small and the wings beat so fast you can hardly see them. I have a few that hang around the feeder and am amazed that they can be stationary in one place or fly off at a fast speed in the blink of an eye.
I read a statement that a hummingbird’s wings move 90 times every second. That makes the wings move 5,400 times every minute. I started to wonder what type of muscle can move that fast. And include the question of what system of nerves to the muscle can handle that fast of a movement. That number of contractions in one second is very hard to imagine. Trying to relate that fast movement to what a human can do in comparison is the realization that humans are very slow-moving.
Human muscle has three major types. There is a fast twitch and a slow twitch muscle fiber and then a middle twitch fiber that can be conditioned to be close to fast or slow twitch. Most humans are about a 60 – 40 ratio of either fast twitch or slow twitch. Most of us are not super-fast moving and can’t sustain that muscle movement for long periods of time. We can work to improve one or the other but never really reach that elite level of movement. Some athletes have a ratio of over 85 – 15 of a muscle fiber component. If the ratio is fast twitch fiber the athlete has the potential to be a sprinter in the Olympics. If the ratio is slow twitch fiber the athlete has the potential to run a sub-5 minute mile pace in a marathon.
Researchers can do a muscle biopsy and determine what ratio of fast twitch and slow twitch muscle fibers you have. They make a small incision and cut out a few muscle fibers to look at under a microscope. This is usually done in the calf muscle. Most people are satisfied with what ratio they have and the thought of cutting out a muscle fiber to find out if they will be fast or slow is not that important. There are other methods to determine your potential in sports. One is an oxygen analyzer test that determines how well you utilize oxygen when you run. I did that test and was told I had the potential to run a three hour marathon. I came within three minutes of my potential and but knew that running a 2:10 marathon was never going to happen no matter how hard I trained. The other test is with muscle movement. To be good at most throwing-type motions you need to be able to accelerate throughout the entire movement and be moving at your fastest at the point of release or contact. My son took a similar test when he was in the eighth grade. He was very fast for most of the movement but reached his full speed about three-quarters of the way through the movement. He did not accelerate the entire distance of the movement. He was told he would never be a good shot putter in track.
Whether you have an abundance of fast twitch or slow twitch fibers will not help you reach your full potential unless you train hard to take advantage of your muscle capabilities. The large percentage of people can improve with training over time. You will get better at your sport but will never reach that elite Olympic level of ability with an average muscle fiber ratio. Some may be a 70 – 30 ratio, others might only be a 50/50 ratio. The medium twitch muscle fibers can help you reach your full potential by either favoring a fast twitch movement or a slow twitch movement. I think I am an average-level fiber composition. I improved from a first marathon time of 3:45 to an above average 3:03 time. I probably have a higher ratio of fast twitch fibers as I did well in Olympic weight lifting that requires fast muscle contraction. By comparison I will never be a hummingbird level type of athlete. I doubt if I will ever be an albatross bird that can fly all day. That leaves me looking at robins, blackbirds, maybe a mocking bird, for comparing my athletic ability to the bird world. But, I still enjoy watching hummingbirds and Olympic athletes to see what it is like to reach that elite level.