Non-textile Suits: Were They Statistically Significant?

As the Summer Olympics approach again, the eyes of the world will turn from the basketball court, baseball field and gridiron to the pool. The storylines will focus on 18-time gold medalist Michael Phelps in what is perhaps his last Olympics and the dominant, 19 year old force likely to take over his spotlight, Katie Ledecky (watch this video of her dismantling world class competition if you haven't heard of her yet). Throughout the Olympics, there will likely be many references back to 2008 when Phelps won a record 8 gold medals. Without a doubt, there will be a replay of the indisputable greatest race of all time, where the American's shocked the top-ranked, smack-talking French team, driven by Jason Lezak who anchored the relay with the fastest 100 meter freestyle split of all time.

A detail that is hard not to notice from that video is the world record line. A whopping five teams ended up breaking the old world record during that race. Over the course of the meet, world records were broken on 25 separate occasions. This contrasts with the 2004 Olympics in Athens where a measly 8 world records were set.

Another difference that an observer with a keen eye will notice between the 2008 Olympics and the Olympics this year, is the lack of full body racing suits. No longer are the American men decked out in American flag-decorated supersuits, but instead are rocking textile jammers that don't extend past their knees or hips. What gives?

In February of 2008, Speedo released the long anticipated LZR racer. Designed utilizing NASA's wind tunnel and fluid-flow analysis software, the suit was marketed as the "world's fastest swim-suit." It featured corset-like compression of the core to help swimmers maintain perfect body position and increase oxygen flow to muscles, polyurethane panels meant to increase buoyancy and had ultrasonically welded seams to reduce drag in the water. Early case studies suggested the suit could single-handedly reduce a swimmer's times by 1.9-2.2% when compared to textile-based swimming suits. That is exactly what the suit did. Within one week of its launch, 3 world records fell. At the Beijing Olympics, 98% of the medals won were by swimmers wearing the LZR.

Within the year, competitors began releasing suits that built off of the knowledge gained by the design of the LZR. These suits were completely covered in polyurethane, conferring a significant amount of buoyancy to the swimmer who wore them. Additionally, swimmers began wearing more than one of these suits on top of each other, trying to gain the maximum advantage possible over their competitors. This lead to swimming purists, and the FINA representatives in charge of international swimming, claiming that the suits were a form of "technological doping" and were detracting from the physical competition. This resulted in the ban of all non-textile suits and the enactment of restrictions about what suits are allowed in competition on January 1, 2010, within two years of the release of the LZR.

As a swimming fanatic myself, this storyline got me wondering if the suits really were that significant and if they have left a lasting impact on the sport. To begin to dig into these questions, I gathered some data on the two events I believe to be the most impacted by the supersuits, the sprint freestyle events. To see if the suits really did change the sport that much, I plotted the world record progression in the men's and women's 50 and 100 meter freestyle events from the 1970's until the present. The graphs I constructed are below:

To me, these graphs are quite illustrative of how the aforementioned "supersuits" changed the sport of swimming. They pass the bloody obvious test of statistical significance showing that the introduction of the supersuits in 2008 was associated with a dramatic drop in the world records that have not been approached since. Across these events, the world record was broken a collective 22 times during 2008 and 2009. Since then, no one has broken the world record in any of the events. Overall, for the 20 swimming events for which a world record is listed, 5 of them have been broken on the men's side and 13 on the women's side since the suits were banned. Additionally, of those 18 combined records, 6 of them came in breaststroke events where a recent rule change on underwater pullouts has significantly reduced times. Therefore, since the banning of the supersuits, only 2 records on the men's side and 10 on the women's side have been broken without other rule changes that affect the event. The reason more have fallen on the women's side is likely that they are still allowed to wear suits that go from their knees to their shoulders, where the men's suits must be between the knees and hips.

It remains to be seen if more records will fall in Rio this summer, but it is clear that the two year period where the supersuits were allowed fundamentally changed the sport of swimming. They are clearly associated with a significant drop in almost all of the world records. Moreover, many of the records set in the supersuit era are likely to stand for a long time. This begs the question, was banning the suits the correct decision by FINA and will we ever see them brought back?

Personally, I believe the ban should be lifted and the suits should be brought back. Watching swimmers perform inhuman feats in these suits was enough to generate excitement about swimming outside of the Olympics. When records were falling so freely, non-swimmers would be enticed to watch meets outside of Olympic years. Now that many of the records are unattainable, I feel that swimming has lost a lot of its attractiveness. Swimming is not a sport like NASCAR where the speeds must be limited (restrictor plate racing) to keep the participants safe. Instead, swimming is the opposite. They should encourage faster races to make the sport more exciting to watch. With the current state of the sport, the suits should be brought back to make the world records attainable again.

Overall, it is clear that the supersuits fundamentally altered the sport of swimming and those effects are still felt throughout the sport today. This issue had, and still has, the swimming community divided. That being said, during the Olympics this summer in Rio, you will find me glued to the screen watching the swimming while repeatedly quoting Frozone.