How To Plan An Ironman Nutrition Strategy

  • By Lauren Antonucci
  • Published Jul 29, 2016
Photo: Kurt Hoy

Q: I’m training for my first Ironman, which is in a month. I have been using a sports drink and eating energy bars and sandwiches on the bike, but I rode with a buddy last weekend who recommended a new nutrition strategy—a mixture of two new (to me) sports drinks. Should I try it?

A: Unless you have been experiencing repeated G.I. distress (gas, bloating, nausea or diarrhea) during or after training sessions with your current nutrition strategy, then no!

I recommend sports drinks that contain both dextrose and sucrose, and extra sodium. The mixture of carbohydrates is important, as dextrose requires no digestion. Although both sugars provide rapidly available energy, they are taken up by the G.I. tract differently, which helps deliver more carbs to your working muscles, and helps maintain energy, pace and performance. Extra salt is crucial to endurance athletes, as we sweat 0.5 to 2-plus liters per hour during exercise, and 500 to 1,500-plus milligrams of sodium per liter of sweat! It’s also a good idea to use a mixture of liquid calories (sports drink) and solid calories (bars and sandwiches).

RELATED: Simple Half-Ironman Nutrition Advice

Most triathletes I work with do better, feel better and experience less G.I. distress during an Ironman event when they take in solid as well as liquid calories on the bike. Thirty to 50 percent of your calories consumed on the bike should come from solid foods. What you can still do at this point in your Ironman prep is to calculate your current intake of fluid, carbs and sodium per hour, and adjust, if necessary, as you fine-tune your race-day Ironman fueling strategy.

RELATED: Dirk Bockel’s Hawaii Ironman Nutrition Plan

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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