Knowing the give and take of muscle composition

Several of my friends were talking about different running events that they had been part of from years ago. Some recalled running track in high school or college and there were a couple that told about running marathons.

Some of the times in their races were above average and a few were just glad they finished the race.

The marathon distance was the one race that having run the distance was the accomplishment that was as important as running it for a time.

Every person has a certain muscle composition and it puts limits on how well you do.

Muscles are classified as having fast-twitch or slow-twitch fibers.

Most people have a combination of both types and can alter the percentage by about 10% to 15% of this combination by training.

The average runner has a 60%-40% of one type over the other. The Olympic class runner that runs sprints might be in the above-85% range of fast twitch fibers. The Olympic marathon runner has the slow-twitch fiber ratio of above 85%. An average person can change the ratio by a few percentage points, but will never reach the level of those with the higher ratios.

In college track, I ran the sprints mostly. I was above average but was never really fast. I was told that I had the capability to run a three-hour marathon. I did a 3:04 marathon which was pretty close to my ability with my percentage of fast and slow twitch fibers and VO2. I could train for years and would never reach a 2:10 time that elite marathon runners can do. The same for being able to run a 9:07-second 100 yard dash. I was an above average runner but would never reach the elite level of running.

While most of us are average in the makeup of fast and slow twitch fibers, we are capable of doing some amazing things with some training. I trained runners to run a 3:30 marathon and most were successful in the challenge. This is not considered a fast marathon time but when you look at the fact that over 50% of marathon runner’s finish in over four hours it is a good accomplishment. And there are those that finish in over five hours. I trained one individual who wanted to walk a marathon in under seven hours. When you think that he walked 26 .2 miles it is a great achievement. And the fact that he was able to walk for seven hours without stopping was another great achievement. I had been training him in weight lifting and he was entering powerlifting meets after a year of training. The training for lifting weights versus attempting a marathon for seven hours required a different type of training.

This is an example of the ability of an average person achieving outstanding levels of performance with what ratios of muscle fiber composition they have. A person will not reach the standards of the athlete that has a high percentage of one type of muscle fiber. And that elite level athlete will not be able to reach the level of the opposite type of muscle fibers. A two-hour marathon runner can run under a 5-minute mile for 26 miles, but cannot run the 100 meters in under 10 seconds. And that 10-second 100 meter runner cannot run close to a two-hour marathon.

There are methods to determine what percentage of fast and slow twitch muscle fibers in a person.

The method usually involves cutting out a sample of your muscle from your calf muscle and looking at it under a microscope. Not many people are willing to give up some muscle fiber in their leg to see if they will be an Olympic athlete. Most athletes know what their ability is when they enter races in track or a road race. A good runner can run close to a five minute pace in a 5K race but can they keep that pace up for a marathon distance. Watching marathon races on TV sees a good number in a pack for the first 10 miles. As the distance increases the pack gradually diminishes until only less than five runners are racing to the last few miles.

While the ratio of muscle fibers is crucial to performance this also holds true for the nerve impulse to the muscle. Shot putters and jumpers have to be accelerating up to the point of release or take off. My son was in the 8th grade and did a muscle performance test. He had good explosive power but reached top speed before the point of full extension of his arms. He was told he would never be a good shot putter. He needed to be able to accelerate for the entire distance.

While most of us are an average ability we can still achieve remarkable levels of performance with what we have.