The Science Behind the X Games

If you read my last article, “Combining Sports, Science, and Athletes,” you know that I’m especially interested in the science and engineering behind what makes some of the most well-known athletes truly extraordinary at what they do. Each semester, I work with professors at universities around the country to develop project ideas that may appeal to electrical, biomedical, or mechanical engineers, and each semester the sports-themed projects always receive the most interest.

With the X Games coming to Austin this summer, I immediately started thinking of the mathematical wonder that is the Big Air Ramp for BMX and skateboarding. This 360-foot long ramp launches riders into the air at 41 to 43 mph over a gap and upwards of 20 feet. As a sports enthusiast and engineer, I’m fascinated by the trade-off that occurs when developing a ramp that must be mathematically sound and take athletes’ safety into account while still pushing the boundaries of this extreme sport.

You’ve seen them: those amazing pictures of athletes soaring higher than what seems humanly possible. For a split second, it seems they may never come down, and spectators are sometimes worried about what might happen when they do. How do athletes like Danny Way, Shaun White, and Bob Burnquist get so high? Are they super human? The answer is twofold. First and foremost, these guys are incredible athletes who train and push their bodies to the extreme, but the second reason is that science is building ramps that help them reach heights never seen before.

While these parts appear to have remained relatively unchanged in 20 years, the ramps have actually gotten bigger year after year. For instance, in 2002, the walls of the Olympics half pipe were 12 feet high. Then, in 2006, the height grew to 15; from there, the half pipe grew to 18 in 2010. At the 2014 Sochi Olympics, the ramp height came in at a staggering 22 feet. What is driving this change, and, more importantly, how does this affect the athletes? To determine why Olympic ramps have essentially doubled in height over the last 12 years, it’s important to look at how a ramp works.

In simple terms, a ramp, like the vert of half pipe, turns speed into height. The goal behind a ramp is to get the most air possible, and so they can be described by the law of conservation of energy, which states that energy cannot be created or destroyed; it can only be transformed from one state to another. In the case of a ramp, the energy changes from potential energy into kinetic energy as the athlete enters and rolls down the ramp. When the athlete rolls up the opposite side and leaves the ramp, the kinetic energy converts back into potential energy. This process cycles through until the losses (due to forces like heat, friction, and aerodynamic drag) stop the athlete. What scientists have done is look for ways to optimize this relationship using geometries that will decrease the amount of energy lost due to friction, thus throwing the rider further into the air.

With all of this interest in sports technology, it’ll be interesting to see how future ramps get bigger and faster yet maintain the athlete safety. Spectators can expect to see some high-flying action at the X Games this year, and perhaps some may happen to stop and think about the science behind the sport. As for me, I’m excited to see how the next generation of athletes and ramps evolve.

How Ramp Design Helps with Speed and Height

• A basic vert ramp (named for the way they change horizontal speed to vertical height) consists of four major sections.
• Flat bottom (the horizontal area at the bottom)
• The transition (a section of the ramp that connects the flat bottom to the vert)
• Vert  (a portion of the ramp that sends the rider into the air)
• Table (a horizontal portion of the ramp that extends from the vert; athletes enter the ramp here and use it as a holding area)