It's getting hot out there—May 2014 was officially the hottest in history—and that's bad news for endurance athletes. If your body isn't adjusted to competing in the heat, you risk suffering from dehydration and heat stroke.
Under these kind of conditions, the body becomes less effective at cooling itself, which can force you to slow down during a race.
"Every molecule of sweat that evaporates from your skin whisks away heat. On a dry day, the evaporation of a teaspoon of sweat could cool your entire bloodstream by 2 degrees F. But as the humidity creeps above 75 percent or so, there's so much water vapor in the air that evaporation becomes increasingly difficult," says Patrick J. Skerrett, executive editor of Harvard Health.
Instead of competing the same way you normally would, change your plan to make sure you have the best finish possible.
The heat affects athletes differently. Body type matters—large build versus lean build—in the heat.
Lean athletes can handle the heat better because they have a greater body surface area in proportion to their body mass. On the other hand, athletes with a bigger build accumulate heat faster than their bodies can shed, and this happens early in the race. This translates to a lower maximum effort for the larger built athlete.
If your body isn't used to the heat, it will damage your performance regardless of size. Consider the places where you can make up time lost as you create a plan for competing in the heat.
The Swim: The water is a great temperature equalizer because it's difficult to overheat in all but the most extreme open-water environments. This is an important spot for the larger athlete to make up for lost time.
The Bike: The high velocity of airflow mitigates the performance-reducing effects of heat. This is an important time for all athletes to put in extra effort.
The Run: This is where it falls apart for many athletes, especially in extreme heat. Studies have shown that various athletic "cooling technologies" don't work as well as advertised, so without airflow from the bike, you're stuck with it. Adjust your pace in order to remain consistent.
It's important to remember that once your body crosses a certain threshold, based on your size and the temperature, the heat inside you continues to build until the body shuts down. The resulting muscle damage can slow you to a hobble for the remaining miles. This phenomenon occurs regardless of your size, so always be mindful of the temperature.
Once you make your plan, fill up the water bottles be mindful of the signs of heat stress. It's important to drink plenty of fluids before, during and after the event.
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