Why Are Sprinters So Muscular?

A lot of people are looking at this topic completely backward. Sprinting itself doesn’t make you muscular. Here are three reasons why sprinters are more muscular than long-distance runners.

Reason #1: Sprinters Are Predisposed to Be More Muscular

But, to build on what he said, sprinters were born to be what they are, which is muscular, and explosive.

There are different kinds of muscle fibers:

The Type II are the fast twitch fibers that you may have heard of.

The fast twitch fibers are explosive in nature and fatigue rather quickly, and therefore are used in short intense exercise like sprinting and weight lifting.

But, here’s the thing, fast-twitch muscle fibers have about double the potential for growth that their slow-twitch brothers have. Therefore, people with more fast twitch muscle fibers (like an elite sprinter) are going to be able to grow more muscle.

So, the way many people look at the “sprinters so muscular and long-distance runners so thin” question is backward.

It’s not necessarily that sprinting made sprinters more muscular. It’s genetics.

The same genetic predisposition that made them a great sprinter, made them more muscular.

Reason #2: Sprinters Train To Be More Muscular

Genetics is a major part of the story, but it isn’t the entire story.

People’s fiber type composition doesn’t vary all that much. To quote an expert on the subject,

The above point is only about the general population. Not the elite-level sprinters and long-distance runners that you may be referring to in your question. We can only speculate the difference in fiber type composition in elite-level sprinters and long-distance runners.

But, as was said, physiological characteristics don’t vary all that much from human to human.

So how would you MAKE yourself a better sprinter?

Based on what I said previously about fast twitch muscle fibers being the kind of fiber used in sprinting, and fast twitch fibers having double the growth potential, it would make sense to try and grow those fast twitch fibers.

And that is exactly what elite sprinters do.

Not only are sprinters predisposed to being more muscular, but they regularly weight train.

The greatest sprinter ever, Usain Bolt

Elite Level Sprinter Tyson Gay

Football players at certain positions could also be considered sprinters. Since they run for short periods and rest in between.

Last year, dozens of prospects in the NFL combine clocked in 40-yard dashes that were under 4.5 seconds, which is RIDICULOUSLY fast.

Reason #3 Long Distance Running and Weight Loss

There’s a concept called energy balance.

Energy balance refers to the balance of how many calories you consume versus the amount you expend.

As you can see, exercise increases the amount of energy you’re putting out every day.

The amount of calories that an elite level long distance runner is expending is off the charts.

Running a mile for a 188 pound man will burn about 135 calories (point taken from Running v. Walking: How Many Calories Will You Burn?)

And long-distance runners are running far more than a mile. Meaning that the amount of energy they use every day is very high, which causes their body to use much of the fat and muscle that they have as energy.

Unless they eat like Michael Phelps.