Born To Run

Not many people would say that they’re natural born runners. In fact, over 90 percent of people who train for 26.2-mile marathons suffer injuries in the process. But modern biological and archeological evidence both suggest that the human body is actually uniquely suited for distance running, in a way no other animal can compete with. The Tarahumara Indians of Mexico can routinely run up to 200 miles over two days through their mountainous homeland, wearing thin sandals, without sustaining injury. Other tribes around the world hunt by simply chasing their prey to exhaustion.

What makes the human body so good at running? And, if we are built to run extraordinary distances, why do modern runners frequently struggle against injury despite all the high-tech footwear and moisture-wicking clothing we’ve adopted?

Specialized Equipment

Some animals may be much faster over shorter distances, but several factors allow humans to run long distances more efficiently.

For one thing, we sweat rather than pant. The numerous sweat glands that cover our body — however problematic we sometimes find them — are incredibility adept at controlling the body’s core temperature. Our lack of fur also allows the system to function, since fur would get in the way of any moisture trying to escape the skin. Animals like horses are extremely fast sprinters, but they will overheat and tire out before a human runner will thanks to this cooling system. According to biologists Daniel E. Lieberman and Dennis M. Bramble in their paper “The Evolution of Marathon Running Capabilities in Humans,” a well-trained runner “can sometimes outrun even horses, especially when it is hot.”

The structure of the human foot also gives an advantage to the endurance runner. The big toe is unusual among mammals in that it is in line with the other toes, rather than diverging like another thumb. This creates a solid springboard for the push-off of a runner’s stride. The comparatively short length of our other toes also help make the human foot a more efficient machine. One study suggested that if a person’s toes were lengthened by just 20 percent, the mechanical work requirements placed on the foot would double.

Finally, the entire musculoskeletal system of the human body interacts in a fascinatingly complex way to give you a smooth, upright and balanced stride. Every muscle, bone and sliver of connective tissue works together to allow you to run. When it comes to powering that interaction, the muscles of the average person can store enough glycogen to fuel about 20 miles of running, according to the New York Times.

Why the Injuries?

If your body has so many features that should allow you to run enormous distances regularly, why have injuries become a fact of life for many runners? A number of factors are involved, say running experts. Since the muscles and tendons involved in running do most of their developing early in life, a largely sedentary childhood — which is becoming more common — can slow this part of the body’s growth.

In addition, artificial running surfaces, such as pavement, do not have the same amount of give as natural surfaces and can put excess strain on your ankles and knees. Thickly padded shoes may also force you to develop an unnatural stride by making it difficult for your foot to bend and creating a heel-first striking pattern.

To avoid injury, start out slow and increase your distance gradually. A good rule of thumb is to add 10% percent each week. Take walk breaks as needed, and focus on distance rather than speed at first. Make an effort to run on a variety of natural surfaces, and select thinner shoes that will allow your foot to work the way it was built to.

Personal trainers, especially those who specialize in running, can help you to develop a proper form. Running clinics and groups can also help you improve your technique.

Have you been able to correct your running form? Tell us about it in the comments!

Sources

http://www.nytimes.com/2009/10/27/health/27well.html

http://www.fas.harvard.edu/~skeleton/pdfs/2007c.pdf

http://jeb.biologists.org/content/212/5/713.abstract