The science of race fueling, part two

Nicole Hackett took revenge on Olympic silver medalist Michellie Jones  Credit: Darren England/Allsport
In part one of this series I gave you a healthy dose of the theory behind race fueling, and now its time to put that information into practice - to learn the specifics of how to best fuel yourself during a race.

For the sake of example, lets look at an Ironman-distance race. Obviously, its crucial to do most of your eating on the bike because youre more fresh, and it is easier to eat while youre sitting. Also, eating during the bike gives your body time to ingest needed calories and to transfer that energy to your muscles.

Race fuel should be strictly regulated and the food should be easily accessible. Easily digestible calories should be handy; I like the idea of taping GU or other gels to your bikes top tube. Just tape down the pull-off tab so that you can rip the gel off your bike and open it by using only one motion. Stick the open end of the package into your mouth immediately, even if youre not ready to eat it all. If you dont, the gel will ooze out of the package and the wind will blow strings of sticky gel onto your legs and arms and handlebars, presenting an extra discomfort you dont need in a day full of discomfort.

During a long-distance event, a good plan is to eat a gel once every 20 minutes. That takes care of 300 calories hourly. One 20-ounce bottle of fluid replacement, assuming it offers 100 calories per bottle (and sodium: a good fluid replacement drink gives you an important gulp of sodium, so as to prevent becoming hyponatremic), gets you up to the max you'll be able to take in.

But dont do the whole ride on gel and fluid replacement alone youll have too much solute and not enough solvent if you dont take in a balanced amount of pure water. From personal experience, youll quickly tire of not having water to cleanse your palate after ingesting sugar-laced gels and fluid.

So, on the assumption that you can take in two to three bottles an hour about half of that being fluid replacement, the other half water you should be fine. Your water intake will go up as your body temperature rises, and as you fatigue later in the ride.

Remember that fluid is the most important nutritional component of your race. You must not allow yourself to become dehydrated everything else in this article becomes moot when you reach a state of dehydration. So try your best to keep your fluid intake up in the earlier miles.

There is a school of thought that fuel uptake, like salt metabolism, is trainable, so as you practice your fueling plan while you train, you can also teach your body to take up more carbohydrates during physical effort. Either way, you need to discover in training what your rate of uptake is so youre not starving yourself needlessly, or riding around with a lot of extra fuel in your stomach.

Also, its not normal to eat when your pulse is 155 beats per minute, and practicing your fueling plan will get you accustomed to what its like to eat during effort.

Even when you practice and get it all down, there will always be unknown variables on the course, which brings us to the disagreeable idea of standing down. I personally believe, perhaps against scientific evidence, that the temperature of the fluid you drink can make a difference in how your stomach reacts.

If I found I wasnt absorbing, meaning I absolutely couldnt get the food down, which then forced me to fall behind on my eating schedule, Id slow down. If that didnt work, I would pull in to the nearest aid station and stand down. Id get off the bike, drink a little cold water to cool my stomach, empty my bottles and refill them with cold water and/or fluid replacement, and eat a gel. Id stay down for two minutes, maybe three. I would give my body the once-over with a cold towel, stretch and just relax. Perhaps Id just gone too hard and standing down would reduce my pulse to a rate that would make absorption and digestion easier.

Three minutes taken earlier in the race might save you 30 minutes or an hour later on. Both Paula Newby-Fraser and Luc van Lierde have won the Hawaii Ironman after a mandatory three-minute stand-down, so that should be enough to convince anyone that standing down is not necessarily detrimental. The key is to use this time wisely, which means taking time to regroup both mentally and physically.

Once you are comfortable with your fueling plan, there is something more to consider the fluid replacement sponsor of your planned race. The Hawaii Ironman has had many different fluid replacement sponsors. Off the top of my head I can think of Cytomax, Exceed, Gatorade, MET-Rx and Internutria, and I am probably forgetting some. Only you will know what brands agree with you, and for that reason I suggest you find out which fluid replacement is going to be used on the course and take that brand on your training rides. If you find your stomach is particular about the choice of fluid replacement, there is a trick my wife and I use that works nicely.

We experimented with this during her final Hawaii Ironman, and it worked like a charm. First, we fitted her bike with a handlebar drinking system, and any such system will do as long as it is refillable on the fly. She had a bottle filled with a 10-1 ratio of her favorite fluid replacement. We had previously determined that two squirts of the concentrate were enough to bring 20 ounces of clear water up to the proper concentration.

She would grab bottles of clear water from the bike aid stations and empty them into her handlebar delivery system. She would drink from that, and at the next aid station, shed grab another bottle of clear water, empty it into the handlebar bottle, and squirt in the concentrate. Using this system, she always had cold water and always had her favorite fluid replacement.

When I did the Ironman in 1981, I was oblivious to fueling needs. We all just raced and made it up as we went along. I remember seeing a spectating acquaintance eating an avocado and sprout sandwich about 80 miles into the ride. I needed something badly, so I ripped it out of his hands and kept going. If I ever do that race again, Ill do it more scientifically. I do like avocados, but theyre not the best fuel source during a long, arduous ride. Besides, theyre hard to tape to the top tube.

Dan Empfield is founder and former owner of Quintana Roo, Inc. He now publishes two popular online portals for triathletes, found at and He can be reached at

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