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.
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. 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.
Beyond the skeleton changes and the changes to the muscles and tendons as a result of the skeletal changes, there are some interesting aspects of the feet specifically that make what we know as running possible. With so much obvious advancement of the human body, why is it that there remain so many different opinions of what running is and means? Our bodies have evolved into running machines. There is a wealth of modern evidence to support this, look at all of the different types of running and the different distances that we humans go. We have ultra-long distance endurance runners, running the distance of multiple marathons in a single go. We have people who never run or try to run further than a few miles. We have people that hate running entirely and can’t stand the thought of walking very far, let alone running.
We are clearly built in a way that enables us to run. There are many of us who take advantage of this evolutionary difference that we have. There are also many of us who choose not to take advantage of it or get injured or in pain when they try to. Why is it so difficult to understand what running is and if we humans are designed for it or not? Perhaps the more recent, in the last forty years or so, evolution of running as a sport and hobby that requires special cloths, equipment, and styles has some insights into our concept of what running is.
The running industry has developed rapidly in the last forty years to accommodate a perceived need to supplement our natural abilities to run. Companies like Nike, New Balance, Polar, Suunto, Brooks, Asics, etc. have all cropped up to sell runners special shoes, heart rate monitors, pedometers, wicking clothing, specialized socks, and watches. Not to be outmatched – the services in the industry are growing just as rapidly as the products have. Running styles like the POSE Method, the Chi Method, and the Newton Running Method have all been created to ‘teach’ everyone to run correctly. With so many supplements to just the motion of running, the definition of running has an opportunity to be even more unique for each individual. For example, keeping your heart rate at a particular level (now that we can measure it in real time on a run), keeping your pace at a particular intensity (now that we can measure pace in real time on a run), or if there are a particular number of steps per minute (as defined by the running style of choice). The running industry, after evolving in such a short time, has added a lot to our individual definitions of running. Despite all of these variances in definition and supplemental tools we use for running, running comes down to feet hitting the ground and moving the body forward. Understanding this motion and how it has evolved must be more important to the essential definition of running. .
According to research by a group of researchers at Harvard, a natural running gait consists of one that includes a forefoot or mid foot landing. This landing style is one that naturally absorbs the impact resulting in a body that does not have to deal with the impact. Examining the modern running shoes themselves, it is easy to see a large cushioned heel which promotes an aft foot landing. This aft foot landing allows the shoe to do several things, including align the foot throughout the stroke, reduce or remove pronation, and provide a level of comfort on the ground. These changes to the landing are counter-intuitive to how the foot itself is designed. The most basic method for testing this is to take your own shoes off and try jogging around. Even in the dirt and grass, this is not a comfortable feeling. Taking it a step further and looking at what happens when the foot strikes is revealing. On an aft foot strike, the ankle is pointing the entire foot upwards and all of the weight of your body is pressed onto the heel. There is no load of your body distributed to the arch of your foot or any other component of your foot. As the rest of your foot begins to land the arch begins to share in the load of the landing and the ankle changes how it is flexing to allow the leg to move forward of the ankle. This combination of loading the arch and changing the flex in the ankle is called pronation. Finally the ankle changes it’s flex again for liftoff and the calf muscles and Achilles tendon shorten, the arch recoils, and the toes flex. This final movement causes the upward and forward motion of the body. Compare that movement to the fore and mid foot strikes (with our without shoes on), the initial landing is somewhere on the outside of the foot, generally centered on the ball of the foot (however, this varies by person and variances in exact landing are made by individuals for comfort). When the foot lands, the ankle is pointing the foot generally towards the ground and the toes are slightly elevated. The ankle begins to flex the heel towards the ground letting the calf and Achilles tendon absorb the load and energy of the movement. Throughout this process of landing, the arch is participating in the load absorption. As the heel lands, the arch fully flattens and pronation occurs. This is roughly the same point in time that pronation occurred during a heel landing; however, this time the pronation is reversed and occurs from forefoot to aft foot. The final movement is also the same; however, there is a difference here as well, at the beginning of the landing, the Achilles tendon absorbed all that energy during the stretch of the heel towards the ground. During the liftoff that energy is released as the tendon shortens just like a rubber band.
With information like this available it is easy to see why running styles and training have evolved in recent years to ensure the art of running is not lost. The one thing that all of the running styles seem to have in common is a focus on body positioning and foot landings. The art component of running certainly rests here on how fluid the landings are, how enjoyable the foot stroke is, and ultimately how the pain is accommodated for. In the example of running with high tech running shoes developed in the last forty years the solution to handling the pain of running is to add cushioning and foot controls within the shoe. In the example of running without the use of high tech shoes that has been developed and refined in our body during the last hundreds of years the solution to handling the pain of running is to slightly adjust individual foot landings and take a break from running when it gets to be too much.
What is interesting about the definition of running as we know it today is that it is a result of two different types of evolution; the evolution of the body and the evolution of the running industry. The evolution of running, at least the portion of running that seem to result in our body being able to run, stems from our ancestors having a need to run long distances during hunts. Over time, this requirement to run long distances to provide food for the family and tribe acted as a cultural motivator for the body to evolve into a more efficient running machine. The running industry, being that it only cropped up in the last forty years or so has not had as much time to evolve, nor enough time to determine how useful the evolution is to our ability to run. What is known about running is that it is unique to every person. There are some generalizations about the form of running, but just like all art is unique to all individuals the movement of running is as well. For this reason, it is important to examine how our bodies are designed to move and what feels comfortable for us when we are running and then look at the running industry to see if there is anything useful there to enhance our natural abilities. There certainly may be, after all humans weren’t meant to fly, but the flight industry has done wonders for our ability to get up into the air and explore, calculators have done wonders for our ability to compute numbers, and plastics have done wonders for our abilities to advance society.
With all of these indicators that our bodies have evolved to run and our desire to enhance that ability, as evidenced by our continued expansion of a running industry, the question of the benefits is left open. Are there any measurable benefits that are a result of running? There are a few things that are not generally argued. Running is something that nearly anyone can do, running is good for the body (lowers HDL, promotes bone strength, and results in a healthier lifestyle at older ages), and the way a body moves and the tools one uses to cause the body to move can vary drastically when one considers what occurs when one runs. Another less explored area of running benefits is the level of life satisfaction and satisfaction of family life. One would think that running; especially committed runners who run a lot would have a lower quality of family life due to their being out running all the time. That doesn’t seem to be the case; however. It seems that runners who are committed to running are runners that have a higher quality of life. This is in line with what has been stated throughout this paper, running is an art that evolved in our bodies over thousands of years.
Running can’t be placed into a neat definition because it is so unique for everyone yet collaboratively based on the same principles. I would say that the definition of running includes your personal implementation of an ancient act that has evolved over thousands of years, it includes how all of the bones, muscles, and tendons work together to cause your body to endure the movement or not, the personal feeling and emotion that is wrapped up in the run, and today may be enhanced and measured by a number of tools in the industry. Obviously this is much different than the common definition of long strides and both feet momentarily off the ground, but running is more than just long strides with both feet momentarily off the ground.