This series is a cross post from one of my other blogs that is all about running (www.runyourage.com). I am working on getting to running as many miles as I am old - which may mean that I never get there as I get older every year. I think I'll be able to add miles faster than years though and eventually get there. Anyway - I particularly enjoyed researching and writing this stuff and wanted to offer it to everyone (even if you aren't a runner)... enjoy (link to original)
Running, or some form of running has been around since the dawn of man. It has been the basis of our transportation, the measure that other modes of transportation were initially compared against, and it continues today to be a method of transportation that is both enjoyable and ever changing. So what is running exactly? What does it mean “to run”? What is it about us humans that causes us to make running is such an important part of life? What is it about us that has developed over time to make it this way? With all of our modern inventions, have we really developed an improved running style or tools that make us better at running?
A common definition that is given for running that I hear referred to or that is inferred in conversation includes the most basic concepts, a rapid movement on foot, with long strides and both feet momentarily off the ground. When I view running, this is certainly not the definition or feeling that I get. Yes both feet are momentarily off the ground, yes sometimes it is fast, yes it is always by foot, but sometimes running is relatively slow. Sometimes running does not have long strides. The problem with the definition is that it could include scissor kicks while jumping in the air, it could include skipping, or it could include hopping like a kangaroo. What are missing are the specifics about how the legs are moving in relation to the rest of the body and how the rest of the body supports the run. If the definition doesn’t match what I see as running, there must be more to it than this simple definition that is commonly used. There must be more information about where we came up with the concept, how our bodies are built to support the concept, and how we have grown into runners. What exactly is running anyway?
Running is a mix of art and a physical endurance, there are many aspects of running such as how your legs and feet move while you are running, what things you wear when you run, how you feel when you run, how you stretch, and how you prepare your mind and body for a run. All of these are equally important attributes of what we consider running. For some the accumulation of all these things results in the concept of running being negative while for others putting all these things together results in an activity that evokes pure bliss and enjoyment of life. Why are there so many differences of opinion and different interpretations of running? After all isn’t it just a faster form of walking? To understand what running is and what is meant by the words “to run”, we need to understand how it is that we move in the first place and how our bodies are designed in relation to running.
Running was something that we humans grew into; our ancestors had big toes that stuck out for grabbing objects with their feet. They had knees that stuck out to the side so they could squat better. Their shoulder muscles were designed to help them hang on to branches and climb trees. If we look at the qualities that are important for running, humans have evolved beyond our ancestors, putting our big toes in line with the rest of our toes and underneath our knees. The knees themselves have been moved underneath the hip so that when running occurs, the muscles and bones don’t need to be stressed as much. This is only part of the story. Our hips, being smaller to get our legs actually in front of us, are also doing something that not even our four legged friends have, it is getting our whole body on top of the legs so that the legs only have to move the mass on top of them instead of trying to balance and move all the weight next to them. This is in line with our spine supporting an upright posture and the back of our skulls providing more balance than most other animals. (Bramble and Lieberman)
The interesting part is the side effects of these changes in the bone structure. With our bodies designed to be erect while running, our ability to suck in air while we run is also better. Our lungs can work to their fullest. The most interesting side effect of our skeletal changes to me is the Achilles tendon; this is the most interesting because of its usefulness in running. In studies of gait analysis, it has been found that when running this tendon acts like a big rubber band, storing energy and releasing it into the stride with every step. This makes a number of things better for running, the most important being that it reduces the amount of energy required to run. The tendons themselves are not a prevalent feature in African great apes, nor are African great apes good runners. This suggests that during the evolutionary process, in addition to the muscular and skeletal changes discussed earlier, changes to the Achilles tendon also contributes significantly to what we view as running. (Sellers, Pataky and Caravaggi) If we were to imagine what it would be like to not have these changes, the tendons, the muscles, and the skeletal structure, we would come up with a different concept of running. Our gait would be different, our body posture would be different, and the amount of exhaustion that we experienced would be different. Essentially all of the components we include in our concept of running would be different.
Bramble, Dennis M. and Daniel E. Lieberman. "Endurance running and the evolution of Homo." Nature (2004).
Goff, Stephen J. and Daniel S. Fick. "Training Levels and Perceived Benefits Of Running Among Runners Commited to Both Running and Family versus Runners Commited Exclusively to Running." Journal of Sport Behavior (1997): 387-397.
Liebenberg, Louis. "The relevance of persistence hunting to human evolution." Journal of Human Evolution (2008): 1156+.
Lieberman, Daniel E., et al. Biomechanics of Foot Strikes. n.d. <http://www.barefootrunning.fas.harvard.edu/index.html>.
Sellers, Irvin William, et al. "Evolutionary Robotic Approaches in Primate Gait Analysis ." International Journal of Primatology (2007): 321-338.