By W. Mitchell
Last Spring semester Andy Tegeder, a graduate student from Renton, Wash., came to Dr. Iain Hunter seeking an idea for his exercise physiology research project. Luckily for Tegeder, Hunter visited Nike headquarters two years earlier and returned with an idea. Hunter?s connection to Nike enabled him to coordinate an ongoing experiment in which BYU?s cross country teams are testing Nike pre-cooling vests designed to prevent overheating in outdoor-sports athletes.
? we were just going to use our lab to do some treadmill testing,? said Hunter, assistant professor in the department of exercise sciences. ?Then Nike became interested in us doing some work and loaned us 13 vests.?
The way the vest works is about three hours before competition athletes swallow a white pill, which is about the size of a ?Mike and Ike? candy. Inside each pill is a thermometer, battery and transmitter. The pill transmits athletes? body temperatures to a device that resembles a calculator. This is to determine the precise body temperatures of the athletes before they wear the pre-cooling vests. Once body temperature is determined the athletes put on the vests, which is loaded with ice packs to keep the body from overheating. The 10-pound vests are worn only during warm-ups.
?The idea is that if less blood flow is needed to cool the body, then blood can be used in the muscles more,? Hunter said. ?That means a lower heart rate for the performance, less energy expenditure and increased performance.?
In 2003, as part of a biomechanics conference, Hunter toured Nike?s labs in Beaverton, Ore. Hunter, a former BYU cross country runner, tried on a pre-cooling vest. Eager to provide the research opportunity for his student, Hunter obtained Nike?s consent, and went to work with the BYU men?s and women?s cross country teams. After receiving promising data in team practices, Hunter and Tegeder decided to try the performance enhancing vests in a race.
?We looked at the schedules for hot and humid areas,? Hunter said. ?Hawaii sounded pretty good.?
Hunter traveled with the women?s team to the Big Wave Invitational. Each runner woke up three hours before the race to swallow the pill. Body temperatures were recorded before the women put on the vests, again just before the race began, and a third time immediately after the race.
?Half of the runners wore the vests and half of them didn?t so we would know if the vest group reacted any differently than those without,? Hunter said.
The results showed that the women who did not wear the vests increased in body temperature from warm-ups to the start of the race, while the body temperatures of those who wore the vests did not change during the same time period. Naturally, all body temperatures rose during the race. However, the women who wore the vests during warm-ups maintained a lower body temperature throughout the race than those who did not.
?Warming up, I was glad I had it on because it felt good in the heat,? sophomore Allison Passey said. ?But I didn?t personally feel any different during the race.?
Senior Sarah Ingebretsen said she didn?t like that the weight of the vest limited her warm-up activity. She said the vest kept her cool during warm-ups, but didn?t take notice of her body temperature after she took it off.
?I didn?t really think about it because I was focused on running,? said Ingebretsen, adding that her final time was on average with her other races.
Passey?s and Ingebretsen?s less-than-enthusiastic assessments coupled with the following week?s results in North Carolina gave Hunter little time to get excited over the statistics in Hawaii. North Carolina?s race showed no differences in body temperatures between the wearers and the non-wearers.
Hunter said the tests are inconclusive because of the many factors that go into high performance sports.
?We do know that getting over-heated can limit performance,? Hunter said. ?If these vests do decrease body temperature than we?ve at least controlled one of the factors that can limit performance.?
Nike is currently in the developing stages of the product, so it won?t be appearing in stores anytime soon. In the meantime, Hunter is waiting to hear back from Nike on his request to keep a few of the vests, which Nike has requested back. He said the results of his tests were encouraging enough that he?d like to follow up and do some more projects.
?We know the vest cools the core,? Hunter said. ?But I?d like to see what?s happening in the legs because we want the legs to be at ideal temperature for performance. I?d really like to find out if it does help performance.?