The Liquid To Solid Ratio Of Calories During An Ironman

  • By Lauren Antonucci
  • Published Sep 8, 2015
Photo: Nils Nilsen

Q: What’s the “ideal” mix of liquid to solid calories during an iron-distance race?

A: With a plethora of drinks, bars, chews and real food options, confusion abounds. First and foremost, I find that simple, easy-to-execute Ironman nutrition plans tend to work best for most triathletes—meaning, training with the sports drink you will be provided with on the course can help tremendously. Using full-strength drinks (not “high-octane sludge” with 500+ calories per bottle, necessitating “water chasing”) will minimize risk of excessive calorie consumption, maximize flexibility on race day and minimize nutrition mistakes for most triathletes.

RELATED: Planning An Ironman Nutrition Strategy

Sticking to 1–2 product lines/foods can maximize glucose uptake and minimize risk of G.I. distress. Most athletes do best taking in 50–75 percent (of their 250–350) calories from full-strength sports drink (such as Gatorade Endurance Formula or First Endurance EFS) to provide a base of all three needed ingredients: fluid, sodium and carbs. Take in the other 25–50 percent of your calories from carb-based bars, homemade PB&J sandwiches, etc.

RELATED: Nutrition On Long Bike Rides

Plan to drink water when eating your solid calories and increase your total fluid and sodium when your ambient temperature rises. Be sure that by race day you can successfully adjust your fluid, sodium and calorie (carb) intake up or down as needed based on environmental conditions. Have a solid nutrition plan A, but also be prepared with plans B and C in case something goes awry (e.g. your bottle goes flying, your bars get lost or your taste buds reject plan A halfway through). Practice your plan in training repeatedly so you can adjust on race day, and your long, hard training will surely pay off.

RELATED: What Fuels An Ironman Champ?

Lauren Antonucci, R.D., is a board-certified specialist in sports dietetics, three-time Ironman and founding director of Nutrition Energy in NYC.

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FILED UNDER: Nutrition / Performance Nutrition TAGS: /

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