Race Day Nutrition

Without a doubt, advances in sports nutrition have enabled athletes to make tremendous performance gains, and high-tech, scientifically-derived products (such as bars, gels and sports drinks) are crucial to top race-day results; however, consider that, during long-course events, triathletes race from the early morning until, in many instances, well into the night. During this time, athletes will miss four to six regular meals and snacks — all while the body churns through up to 500 calories per hour.

Thus, balanced, well-planned nutrition is required to make up for these missed meals and provide the fuel needed for a race-day effort. To supplement their intake of bars, gels and sports drinks (which typically constitute the core of most athletes’ race-nutrition plans) and provide some culinary variety, many athletes turn to low-tech solutions.


Race-day fuel

So how do you fuel up effectively to sustain a long, intense effort?

Carbohydrates: It’s not practical or necessary to eat as many calories as you’re burning as long as you’re well trained and have topped up your glycogen stores before the race. During an endurance event, your body will burn a mixture of fat and glycogen for energy. The glycogen comes both from your body’s stores and from the carbohydrates you consume during competition.

How much glycogen you use, and how many grams of carbohydrates you require to supply your energy needs, depends largely upon your intensity.

The higher the intensity of exercise, the more difficult it is to eat and digest food; for this reason, it’s important for athletes to know the pace and caloric-consumption rate they can sustain for the total amount of time they’re on the course.

As a general rule, you should aim to consume one gram of carbohydrate per kilogram of body weight per hour during Ironman racing. For example, a 70-kilogram athlete needs 70 grams of carbohydrate per hour; this can come from drinks, bars, gels and real food.

Fat: Fat consumption should be kept to a minimum during an Ironman. Although most of your energy does come from fats at Ironman race intensity, your body stores more than enough fat to supply this energy. The limiting factor in Ironman performance is carbohydrate availability, so carbs should be your primary nutrition focus.

Also, any fats you consume will tend to slow digestion and metabolism; therefore, food choices need to be ultra-low fat and high in carbohydrates so sugars can get into the bloodstream as quickly as possible without extra caloric expenditure.

Protein: As with fat, most of the protein used for energy during exercise is already in the body when you begin your race. That said, some studies have indicated that protein consumption during exercise can boost endurance, not so much by providing a direct energy source as by reducing muscle damage.

Sodium: Athletes need to ingest sodium to replace what’s lost in sweat and to help with hydration. An athlete can replace 500 to 700 mg of sodium per hour with salt tablets and salty foods.


What to eat during your endurance distance race

When choosing foods for a long-course race, look for ones that are low-fat, low-fiber and high-carbohydrate. Below are several common foods that athletes can use on race day to supplement the supplements, either to help meet nutritional requirements or simply to give the taste buds a break. By way of comparison, a 63-gram PowerBar Sport energy bar has 2.4 grams of fat, nine grams of protein and 41 grams of carbohydrate.

  • Bananas have it all, plus good packaging. A banana has 140 calories, no fat, 36 grams of carbohydrates and three grams of fiber. Other fruits that pack well and have high carbohydrate values include dates (31 grams for five dates) and raisins (31 grams for a quarter cup). Dried prunes, apricots, figs and apples are not recommended because of their higher fiber content and a relatively low glycemic index.
  • Not just for Aussies: Vegemite doesn’t have much in the way of fat, calories, carbohydrates or fiber, but it does pack a good sodium punch: 200 mg for a four-gram serving. And who knows, maybe Vegemite tastes good at 120 kilometers into the bike.
  • White bread and bagels have a high glycemic index and low fiber content. Basic white bread has 12 grams of carbohydrates per slice and less than a gram of fat. Eat it plain or add a small amount of almond or peanut butter and jam, Vegemite or bananas and honey.
  • Some vegetables make good Ironman foods. A small salted, steamed potato with the skin off (the skin has fiber) has about 15 grams of carbohydrates, no fat and only two to three grams of fiber. For another savory taste try boiled, salted parsnips cut into chunks or sticks. Half a cup of parsnips contains 15 grams of carbohydrates, and the high glycemic index means this food will go to work quickly.
  • While chocolate bars and most cookies have too much fat to be of much use for quick and sustained energy, sometimes you just need a chocolaty tidbit to look forward to in your special-needs bag. A small portion of animal crackers, Arrowroot cookies, jelly beans, chocolate or Nutella spread thinly on white bread can give you a taste-bud break.


The logistics of lunch on the fly

Packaging, storage and ease of delivery are important considerations when selecting foods to use during a race. You need to have the full food portion available for consumption (not squashed all over your bike-jersey pockets), and it has to be easy to consume (small bite-size pieces in a plastic bag or wrap).

Make sure you can open your snacks while your heart rate is 160 and you have one hand on the bars. Food that’s spoiled, melted or too cold will not be eaten, leaving you short on calories.

It’s important to be fairly systematic about fuel and fluid consumption. Based upon your training and previous race experience, you should figure out your eating plan and try to stick to it. According to sports nutritionists at the Australian Institute of Sport, you should view the bike leg as a rolling buffet for your food and fluid intake. It’s easiest to eat on the bike, and you should look at the bike leg as a way to set you up for the run, where your caloric intake will be significantly lower.

Also, know and use the course to aid your eating. Take advantage of hills, tailwind sections and flat areas where you can spin for a bit. Be aware of factors that limit your caloric intake, such as bad weather and just feeling off, and be extra diligent about getting in what you need. Once you’re on the run, you may have to walk through aid stations in order to ingest food and get something to drink.

It cannot be stressed enough: Practice eating in training what you plan to eat on race day. Include in your training the foods you want to consume, experiment with quantity and pay careful consideration to transport and ease of delivery. Chances are your dad isn’t going to be there at the start of the race with a steak sandwich, but if he is, make sure you’ve eaten a few in training.




It’s all about carbohydrates

Without question, carbohydrate is your body’s most efficient fuel source, and extensive research supports the role carbohydrate plays in both low and high intensity endurance activities. As an endurance athlete, be aware that your body has a limited carbohydrate storage capacity. The quantity of carbohydrate stored in the body (as glycogen) is directly associated with, and modified through, the diet and level of training. If you consume a high carbohydrate diet you will naturally store more glycogen. Moreover, your body is more inclined to store additional glycogen during your Ironman training months as compared to a short course race season.


For example, a 150-pound triathlete can store approximately 1800 calories of glycogen as carbohydrate: 78% stored in the muscle, 18% in the liver and 4% in the form of blood glucose. This fuel source can support up to two hours of high-intensity or four hours of moderate-intensity training. Our body can also utilize fat and protein as fuel (in very small amounts) to support the moderate-intensity workouts at the heart of Ironman training, but our stores are clearly inadequate to support the energy demand of 4+ hour training days.



How does carbohydrate intake during training help performance?

Consuming carbohydrates during training sessions of longer than one hour can enhance performance by maintaining adequate blood glucose (sugar) levels. Blood glucose is the main fuel source for your brain, and a well-nourished brain may improve your training focus and possibly decrease your perceived effort. During the later stages of long training sessions, when the body’s carbohydrate reserves are running low, the greatest contribution to improved performance is achieved through maintaining steady blood glucose levels. Carbohydrate intake during training cannot prevent the inevitable fatigue associated with Ironman training, but it can prolong its onset.


It‘s important to note that athletes who neglect a sensible fueling plan during training may be placing themselves at risk for progressive muscle glycogen depletion. Over the course of the training week, these athletes are slowly depleting their carbohydrate reserves by continually under-fueling their workouts (e.g.: going for a three hour ride while consuming only water and two gels). The result of this glycogen depletion is unnecessary muscular fatigue and poor quality or “flat” workouts. Chronic glycogen depletion can easily be avoided by maintaining a diet of adequate daily carbohydrates AND consuming carbohydrates during your training sessions.



How much carbohydrate is needed during training?

Scientific studies estimate the range of dietary carbohydrate at 30 to 60 grams per hour. Research has shown that the human body can only burn (oxidized) carbohydrates at a rate of 0.5 to 1 gram per minute. From practical “real world” experience, I know many athletes who tolerate amounts higher than this …even as high 100 grams (or about 400 calories per hour).


For training sessions lasting longer than one hour, I recommend athletes strive for 45 to 75 grams of carbohydrate per hour. This can be divided in to two to four doses (consumed every 15 to 30 minutes). Smaller athletes should start at the lower, and larger athletes at the higher, end of the range.


Your ability to tolerate and/or absorb a particular amount of carbohydrate may be influenced by the type of carbohydrate consumed, the intensity of activity, and your hydration status. For instance, some athletes can tolerate a high-glycemic, sucrose-based sports drink, while other individuals may better tolerate a lower-glycemic, maltodextrin-based drink. Keep in mind as training intensity increases the stomach’s ability to handle high-carbohydrate loads decreases.



Things to consider when experimenting with your training nutrition:

1. Carbohydrate quantity and tolerance may vary from one session to the next. Establish a carbohydrate intake range that will support sessions at various durations and intensities.


2. Carbohydrate sources in the form of solid, gel or liquid are all effective in supplying energy. When utilizing gels or solids, consume eight oz. of water for every 10- to 15-grams of carbohydrate consumed. It’s best to stick with a sports drink or gels during high intensity training sessions.


3. If you can’t tolerate consuming carbohydrate during moderate to high intensity workouts of 60 minutes or less, ensure you have a high carbohydrate snack (providing 0.5 to 1 gram of carbohydrate per pound bodyweight) one- to two-hours before the workout.


4. As the temperature climbs in the summer, your hydration and electrolyte needs will also increase (we’ll address this next month). A sports drink can be the best choice for meeting a majority of your carbohydrate, hydration and electrolyte needs.


5. To determine the quantity and types of carbohydrates that work for you, maintain a training food log. Record what you eat and/or drink during training sessions, especially those last longer than three hours. Make notes on the quality of your workout and any possible GI issues. This will be a very helpful reference prior to formulating your race day plan.


EXAMPLE Training Food Log Entry


Saturday: 3 hour ride ~20mile per hour average

Hour Hourly intake

1 24 oz Gatorade (42gmCHO)

1/3 PowerBar (13 gm CHO) + 12 oz water 63 gm Carbohydrate (CHO)

36oz fluid

2 16 oz Gatorade (42gmCHO)

1 Gel (20 gm CHO) + 16 oz water 28 gm CHO

32oz fluid

3 24 oz Water

1 Gel (20 gm CHO) 20 gm CHO

24oz fluid

COMMENTS: Felt strong first half of ride but fizzled at the end. Tried new energy gel…no GI problems. Very warm day, Pre weight: 130# Post weight: 128#.

****Need to work on better fuel and fluid intake next ride.

Total carbs 111gms or avg 37 gm/ hour. Total Fluid 92oz or avg 31 oz/hr.



The main goal of your fueling program during training (other than maintaining hydration) is to provide a steady stream of carbohydrate from mouth, to gut, and into the blood stream. Maintaining a well-fueled body before, during and after training will maximize the cumulative effects of each training session. Getting the most out of each session adds another layer of confidence in your journey to go the Ironman distance.