How Does Ironman Know When Athletes Enter the Water?
When entering the water, athletes will go under a swim start arch at the water's edge. Timing mats are underneath the arch, which will trigger the timing chip athletes will be wearing.
Is There Still a 2:20 Time Limit in the Water?
Yes, the swim course doesn't close until 2:20 after the last age group athlete enters the water. But if your swim time exceeds 2:20, you will be disqualified.
Is the 17-Hour Time Limit Still in Place? Does the Famed Midnight Cutoff Still Have Meaning?
Yes, the 17-hour time limit is still in place. And the midnight cutoff still has some meaning.
Swimmers begin to enter the water at either 6:30 or 6:35 a.m. (depending on the race) and Ironman officials expect everyone to be in the water no later than 7 a.m. If that's the case, nobody would be able to finish both after midnight and under 17 hours.
However, it is now possible for an athlete to finish before midnight and still be over the 17-hour limit. If that's the case, the participant would not be recognized as an official Ironman finisher.
Is Every Ironman Race Going to Do This?
So far, these changes are only being tested in North America, and only at certain events. In 2013, only Coeur d'Alene, Lake Placid and Lake Tahoe are doing rolling starts. Ironman Florida will have a mass start based on self-seeding in different corrals to put athletes among other similarly skilled swimmers. Ironman Mont-Tremblant in Quebec will feature a wave start based on age group (eight waves starting five minutes apart). Ironman will assess the success and feedback of all three of these methods before implementing any of them in 2014 and beyond.
Texas, Wisconsin, Arizona and Canada will continue to have mass starts. The Ironman World Championships in Kona will also have a mass start.
Here's a video of the rolling swim start at Ironman Coeur d'Alene:
More: 2 Swim Sets for Speed
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