Carb needs for different exercise durations


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Today’s Globe column brings together a few recent topics of discussion from the blog about carbohydrate needs for short, medium and long exercise bouts:

The question

How long can I go before I need to “refuel” with carbs, and how much do I really need?

The answer

If you’re spending nine hours doing an Ironman triathlon, you definitely need fuel. Samantha McGlone, the 2007 World Championship silver medalist, downs five sports drinks during the bike ride, and adds one or two energy gels an hour to her drinks during the run.

“But I have done Olympic-distance races [which take about two hours] on water,” says the Montreal native, who represented Canada in triathlon at the 2004 Olympics. “Maybe not the best, but back in the day …”

Researchers have been arguing for years about whether carbohydrates make any difference during exercise lasting an hour or two and, if so, how much you need. Recent experiments suggest that during shorter workouts, carbs are for the brain rather than the muscles, and that during longer workouts, not all carbs are created equal… [READ THE WHOLE ARTICLE]

Also worth checking out is Trish McAlaster’s nice graphic that accompanied the article, based on information provided by Asker Jeukendrup:


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