Today in Rio, CU Boulder’s own Emma Coburn won the Bronze Medal in the Finals of the Steeplechase, a 3000 meter race over barriers and water. To complete the race, competitors run seven and a half laps on a standard 400 meter track. Each lap has five wooden barriers which, unlike hurtles, do not move when runners crash into them. The fourth barrier in each lap is followed by a water pit 12 feet long, and two and a quarter feet at its deepest. In a single race each runner encounters 35 barriers, including the 7 water pits.
I ran the steeplechase as a Division III athlete in college, and made huge improvements over a few short years, but even if you took me at my prime and put me in a race against Coburn, I wouldn’t stand a chance. To get a clear idea of what makes Olympic runners able to perform so highly, I talked with former CU Steepler and Olympian Shalaya Kipp, a rising third year graduate student in Rodger Kram’s Locomotion Lab, who also placed 4th in the 2016 US Olympic Trials for the steeplechase in July.
Kipp studies the forces acting on athletes as they hurtle the barriers in the steeplechase, with the intent of decreasing injuries sustained by repeated jumps over the barriers. She has also helped design and conduct experiments to test whether athletes approach and hurtle wooden barriers differently from the lighter, plastic hurtles used in the hurtle events, and if the differences in approach have an effect on a runner’s athletic performance. I talked with Kipp about what happens in our bodies when we run (or perform any physical activity), and how elite runners use this biological knowledge to improve their performance to Olympic levels.
We all know running takes a lot of energy, and this energy comes from the fat and carbohydrates our body stores from the food we eat. The process of releasing energy from food is a term I first heard in my high school biology class: cellular respiration. Our bodies break down, or ‘burn,’ large, complicated fat and carbohydrate molecules in a chemical reaction that creates water, carbon dioxide, other small molecules called metabolites, and a lot of energy. If you haven’t taken a biology class before, this process still might sound familiar because it is exactly the same chemical reaction that happens in a burning fire.
If you are wondering why people don’t spontaneously burst into flames while doing physical activities, it’s because our bodies are very good at controlling the reaction so that the stored energy is released more gradually and efficiently than a fire. In this direct analogy, the metabolites your body creates are the equivalent of the soot and ash created when a fire burns. They are the products of cellular respiration when your body doesn’t have enough oxygen. When our bodies do have enough oxygen (which is not the case when performing a strenuous physical activity like running), our muscle cells can generate much more energy from the same starting products, while also creating fewer metabolites. If you have ever wondered why running makes you out of breath, it’s because your body is trying to get as much oxygen as possible to your muscles.
With this in mind we can better understand some of the adaptations our body makes when we start running consistently. In order to increase the amount of energy we can release from our food, the cells in our bodies will make more cellular structures that carry out cellular respiration. Our blood will get thicker and more efficient at carrying large amounts of oxygen around the body so that more energy can be released from cellular respiration. Also, our hearts will get bigger, stronger, and develop a slower more efficient rhythm so that it can pump more oxygen-carrying blood with every beat.
As we continue to zoom out from the cellular level to examine what is happening when we run, let’s consider what happens in collections of cells, specifically our muscle tissue. Every time our foot hits the ground, the muscles in our legs contract, allowing us to exert a force on the ground which accelerates us forward. Now, Newton’s Third Law of Mechanics says that if we are exerting a force on the ground, then the ground is also exerting a force on us, and this force causes tiny tears in our muscle tissue.
Throughout a workout, these micro tears accumulate in our muscle tissue along with all the metabolites from cellular respiration. In order for our bodies to repair and rebuild themselves to be stronger than before, the metabolites need to be flushed away, as these molecules inhibit the recovery process that repairs the micro tears. Since the workouts elite runners complete are so intense, recovery is just as important as the workout when it comes to improving athletic performance to an Olympic level. If an athlete doesn’t fully recover from their workouts, then they are actually damaging their bodies more than they are strengthening them, and their performance will deteriorate instead of improving.
Elite runners have some tricks up their sleeves to help speed up recovery, but they all essentially do the same thing. One of my tricks in college was taking ice baths after workouts. The cold temperature (50-55 degrees Fahrenheit) speeds up recovery by reducing the inflammation caused by the micro tears. The cold also causes your blood vessels to constrict, helping to flush out the left over metabolites. A more effective recovery technique is called a contrast bath. While taking a contrast bath, you switch between a hot bath which dilates your blood vessels and cold bath which constricts your blood vessels, creating a pump-like effect that, in addition to flushing out metabolites, brings a lot more fresh blood carrying the nutrients needed to repair the muscle tissue into your legs.
Compression is another method for expediting recovery. The thought is that by wearing specially made compression socks or tights, you can also force blood and metabolites out of your legs. One final trick is elevation. Raising your legs above your heart (for example, by lying with your back on the floor and feet resting against a wall) will help to drain blood and metabolites out of your legs. The recovery pneumonic to remember all this is RICE (Rest, Ice, Compression, Elevation).
Of course, nutrition also plays a huge role in recovery because what you eat is what your body uses to rebuild itself. For this Shalaya has us covered with a food blog that you should check out, whether or not you are an athlete!
By Nate Crossette
Science Buffs 