#### Wednesday, February 2nd, 2011...6:32 pm

## X Games: X is for Math

Over the past 6 months, I’ve periodically been contacted by the ESPN program Sport Science, which airs pieces on the science behind sports, to give mathematical advice related to developing segments. This past summer and fall, I helped with pieces related to the World Cup and the Home Run Derby. Just over a week ago, I received an email from a producer of the show. Frankly, my heart rate increases simply seeing such an email in my Inbox as I know 1) the question will be challenging else their team would have answered it and 2) they will need an answer ASAP or as they often comment, “It’s TV, we needed the answer yesterday.”

The problem required predicting the velocity of a snowboarder in the X Games necessary to complete a trick called the triple cork. A model that could answer such a problem would clearly require computations from physics as a variety of variables such as friction (of the snowboard against the snow) and angular velocity (as the snowboarder spins) were inherently necessary to produce meaningful results. Knowing this, I quickly emailed Daniel Martin, who, just this December, completed his requirements for a degree at Davidson. Daniel majored in math and was all but one course short adding a double major in physics. I emailed Daniel in the evening and stated that if he was interested in collaborating, we could meet the following morning.

When I arrived the next morning, Daniel was sitting at the computer in the common space outside the offices of the Math Department faculty. He smiled and said, “I have some things for you to look at.” Daniel, overnight, had completed almost all the work. I worked through his work with him and, in a sense, became a mathematical cheerleader, of sorts, as he zipped through the computations! We discussed a few temporary hurdles that soon were overcome. As I was about to leave for a morning meeting, I said to Daniel, “I need to email ESPN. Will we have a number by noon? That would enable them to have it by 9 AM on the west coast.” Daniel replied, “Yes. I’ll have the answer is about 10 minutes. I’ll prepare a PowerPoint document to explain what I did.” I emailed the TV Producer as I headed off to my meeting.

By the time, I returned, Daniel and the TV Producer were in contact over the phone. His initial results helped the group at Sport Science think through a different way to present the conclusions. So, he needed to redo his calculations. It took part of his afternoon but soon, he had all the desired results. The TV Producer emailed to comment how helpful he had been and that the segment would air during the X Games. How exciting for us both!

This alone would have been a very satisfying story as the TV segment did appear and Daniel’s work appears throughout the piece which can be viewed below:

However, the story continues! Interestingly, Daniel and I didn’t know, in the beginning, if the wish was that our calculations would demonstrate that a triple cork was or was not possible. In fact, we both thought the point would be that such a trick was indeed not possible. However, as we looked at the emerging results, it became clear that the trick was possible. At one point Daniel even laughed, “Here we are two mathematicians sitting at a computer telling some snowboarder that he really can do it!” We both laughed and then regained focus and dug deeper into the model. What were the simplifying assumptions? Did we believe our steps? Were we making any assumptions that might result in a model that was too simplified? We walked through the results several times and in the end decided, “Yes, it does appear possible.” In the later communications with Sport Science, it became clear that the intuition of their group was that it was probably possible. I, for one, was pleased that Daniel and I didn’t enter the results hoping for such a result.

So, in the end, Daniel sent off his work to Sport Science. It was most pleasing to see the piece air during the X Games. And then, on Friday evening, Torstein Horgmo completed the first ever triple cork in competition, as predicted by Sport Science and the calculations of a talented student at Davidson College. What a wonderful moment! For me as an educator, it is a story that I will tell to underscore how mathematical models can predict behavior and how such calculations sometimes take time, unravel new questions, and are not entirely clear how to solve when you begin. You can view the moment below:

## 31 Comments

February 2nd, 2011 at 6:47 pm

That is simply a terrific story.

September 1st, 2011 at 10:29 am

We were in Vail for the X-Games a couple years ago and had a blast, we had press passes and even had an opportunity to interview some of the riders.