Craig Alexander’s Aero Helmet Test

With wind tunnel testing done, Crowie is testing helmet ventilation on the Queen K.

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With wind tunnel testing done, Crowie is testing helmet ventilation on the Queen K.

Three-time Ironman world champion Craig Alexander raced in a Giro Advantage 2 in Kona last year, his first time in an aero helmet on the Big Island. The strategy worked—he PR’ed the bike split and still had enough left to win the race in a new course record.

Before finishing fourth at the 2010 Ironman World Championship, he didn’t preoccupy himself with aerodynamic performance; instead Alexander stuck with the strategy he used to win his first three world titles. He prioritized cooling and fueling above all else and his helmet selection epitomized his approach. While seemingly every other male Kona contender raced in an aero helmet, Alexander opted for a fully vented road version. Since that race in 2010, Alexander has abandoned that strategy in favor of a more balanced approach. He and his coach/performance advisor Mat Steinmetz now analytically approach every equipment selection decision, and Alexander is once again looking at his helmet as a way to gain an advantage.

Earlier this year, Alexander and Steinmetz went back to the A2 Wind Tunnel to test aero helmets for the second year in a row to see if the Advantage 2 was still Alexander’s best option. He is not tied to a helmet sponsor, putting the defending champ in a unique position to pick the best option without any concern for financial commitments.

The original aero helmet test from 2011 showed that Alexander’s head position has a major influence on his aero resistance and even which helmet saves him the most drag. Effectiveness of various aero helmets is dependent on the rider, and Alexander found that the Advantage 2—Giro’s old model—was better for him than the Lazer Tardiz and Giro’s newer creation, the Selector. With the Advantage 2 in hand, Alexander and Steinmetz returned to the A2 tunnel to compare Specialized’s TT2 helmet and a brand new option, the S-Works + Mclaren TT helmet. This helmet is smaller in profile and less vented than the TT2.

Sitting it one position for 112 miles is impossible, so Alexander tested all three helmets in multiple head positions to get an overall view of the performance he can expect in a race. “The TT2 on Craig actually tested a little bit better than the Advantage 2,” reported Steinmetz. “I could probably have manipulated the Giro, like gotten him into a size small,” but they decided the TT2 would replace the Advantage 2 as the semi-vented aero helmet in his quiver.

Results from the S-Works + Mclaren TT trials complicated things. Extrapolated over the course of an Ironman, this helmet has the potential to save about two minutes. It tested substantially faster than either of the other two, but its ventilation is limited. Specifically, it lacks a cut on the front of the helmet just above the forehead. Alexander has relied on that opening in the past to pour water over his head for the cooling effect during hot races. Like in 2010 when he decided to race a road helmet rather than an aero option, Alexander was once again faced with the choice between the faster helmet and the more vented helmet.

Steinmetz looked for the answer to this conundrum in the research literature and through personal connections with scientists. He found, “a lot of times you have a perception of being hotter in the aero helmet but there is a lack of science” showing an increase in core temp. “Research in other fields—military, construction workers and equestrian—showed that participants feel hotter wearing a helmet. The perception is that you always feel hotter with it but it does not increase your body’s core temp. There is newer research on aero versus vented helmets and they’re finding the same thing.” Although the study on cyclists is not yet complete or published, the findings seem to show that helmet selection influences a person’s perception of heat without necessarily raising core temperature. One shortcoming of this information, however, is that the study was not conducted during a eight-plus hour event. They needed more information.

Alexander headed out for his ride during the heat of the day on Saturday, Oct. 6 wearing the Specialized TT2 while Steinmetz rode along on a scooter carrying the S-Works + Mclaren TT. Alexander was doing a race-intensity workout, and the pair used the opportunity to see if he could perceive a difference in temperature between the two helmets. He wore each for between 40 and 50 minutes, switching periodically instead of wearing one for the first half and the other for the second half since changes in weather and fatigue could influence Alexander’s perceived temperature.

They ran into a problem with their test. “It was not hot,” said Steinmetz. “It wasn’t the kind of info we were looking to find because it wasn’t hot enough. It was very overcast almost the entire day and on the way back in we were even getting sprinkled on.” Although they were not able to get a definitive answer, the Mclaren passed this first test.

“The conclusion was that he couldn’t tell a difference,” said Steinmetz, so they will re-attempt the experiment during another ride to see if hotter temps bother Alexander while wearing the S-Works + Mclaren helmet. If that is the case, they will shelf the slightly superior aerodynamic performer in favor of the cooler option.

“I’d like him to ride the Mclaren because I know it’s faster but I don’t want him to ride it to the detriment of sweat rate, comfort and heat perception because it still weighs on your mind.” said Steinmetz. “He understands that the aero helmet is faster and he can’t give that away, but wearing something like the Mclaren is like going from one extreme (a road helmet) to the other.” Whichever crown the current king of Kona chooses to wear, he will make his selection armed with hard data and his own perceptions.

RELATED VIDEO: The Evolution Of The Aero Helmet

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