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How Triathlon Training Nutrition Works


Half-Ironman Nutrition
Although hydration is clearly important, drinking too much can make you sick.
Although hydration is clearly important, drinking too much can make you sick.
©iStockphoto.com/mbbirdy

Next on the triathlon ladder is the Half-Ironman, officially known as Ironman70.3. There are a number of races that may cover the same distances as the Ironman70.3 or the full Ironman events, but unless they're officially sponsored by the Ironman Organization, participants usually refer to them as half- or full-distance triathlons. The Half-Ironman distances break down as follows:

  • a 1.9-kilometer swim (1.2 miles)
  • a 90-kilometer bike ride (56 miles)
  • a 21-kilometer run (13.1 miles)

Since the Ironman70.3 bumps the cycling leg up to 56 miles, let's focus on that. The cycling part of any triathlon offers a major benefit, in that it's the easiest of the three legs in which to grab your necessary food and hydration. Staying away from dehydration is crucial, so you should probably drink as much water as possible, right?

Not so. As important as it is to stay hydrated, becoming over-hydrated can lead to a problem called Exercise-Associated Hyponatremia (EAH). EAH means that your blood's sodium level is abnormally low. It can occur in cases where athletes drink far too much water at one time, thereby flooding the body with more than it can process. But EAH can also occur in instances where the body is retaining even moderate amounts of excess water, instead of releasing it through perspiration or urination. The effects EAH can have on your body are numerous, and sometimes quite serious, so pay attention to the symptoms. Weigh yourself before and after your workout; if you've gained weight, that's a warning sign. Feeling bloated is another indication that something's awry, as are indentations left by your waistband or socks. At the first sign of overhydration, call your doctor [source: UltraCycling.com].

Got your fluids under control? See the next page to learn about the most iconic triathlon out there.


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