BOSTON (CBS) - Major concerns over extreme heat forced the Boston Athletic Association to take a nearly unprecedented step on Saturday.
The BAA announced that competitive runners who have qualified for this year's marathon but choose to skip the race will be able to carry over their qualification to the 2013 Boston Marathon.
Race organizers are also advising bandit runners, those without bibs, to skip the run. They say there will not be enough personnel to handle the extra runners and they want the medics to be able to give their full focus to the 27,000 official runners.
The BAA is also advising out-of-shape runners, inexperienced runners, and any with preexisting medical conditions to consider opting out of this year's race, saying the heat could pose a serious health hazard.
"We are now making the recommendation that if you are not highly fit or if you have any underlying medical conditions (for example-cardiac disease, pulmonary disease or any of a number of medical problems), you should NOT run this race," the BAA statement read. "Inexperienced marathoners should not run."
The BAA also says runners who have only trained in a cooler climate and may not be acclimated to the warmer weather should also consider not running.
Runners who are intent on participating should use caution. To accommodate the expected slower pace, the marathon finish line will stay open an hour later than normal.
"It allows for an additional 2 minutes per mile to slow down and be sensible about it. Be part of what could be a well-remembered experience, but do it in a way that is careful. Ultimately it is an individual sport and individual decision, but we want to make sure we provide people with the comfort of knowing they can make the decision," said Tom Grilk Executive Director of the Boston Athletic Association.
The BAA recommends "For those very fit athletes who decide to run, you should take significant precautions:
Run at a slower pace and maintain hydration. You should frequently take breaks by walking instead of running.
This will not be a day to run a personal best. If you choose to run, run safely above all else. Speed can kill.
Heat stroke is a serious issue and is related to intensity of running as well as the heat and humidity."
Race organizers recommend runners frequently hydrate themselves in order to help keep body temperature down while being careful not to overhydrate.
"Stay hydrated, but don't over hydrate," Dr. Pierre d'Hemecourt said. "Recognize the signs of heat stroke like confusion, headaches and nausea. And if you are feeling sick simply stop and ask for assistance."
Wear lightweight, light-colored clothes. Avoid drinking caffeine, alcohol or tea, as this may lead to dehydration.
Some runners are planning to carry backpack pouches that can hold up to a few liters of water, while others say they're going to go easier than they would have under cooler conditions.
In the 2004 Boston Marathon more than 1,100 runners became dehydrated. Many runners collapsed in the middle of the race and medical tents were completely full.
At the Boston Marathon Expo runners stressed their concern for this year's race.
"I am extremely nervous. I've tried to block it out. I am adjusting my goals a little bit," runner Eddie Carson said.
"Start slow and then speed up is my gain plan," runner Cathy Kemmer said.
WBZ-TV's Paul Burton contributed to this report.
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