Good triathlon nutrition advice starts with preparation. Keep the five Ps in mind – Proper Preparation Prevents Poor Performance. Don’t let months of hard training come undone during race week or on race day by neglecting your nutrition and hydration strategy.

If you are racing an upcoming 70.3 or Ironman event, you should already have trialled and practised your planned race-day nutrition during training. Testing your strategy over several weeks helps you understand what works for you and gives you time to fine-tune it before race day.

Many athletes come unstuck because of poor nutrition choices. Some do not consume enough energy, while others take in too many calories or use products they have not properly tested at race intensity.

Carbohydrate Intake for Triathlon Training and Racing

A commonly used guideline is that athletes can absorb approximately 60–90 grams of carbohydrate per hour during prolonged endurance exercise. However, everyone is different, so your intake should be tested carefully in training.

Many sports nutritionists use a guide of around one gram of carbohydrate per kilogram of body weight per hour of racing. For example, a 70 kg athlete completing a three-hour half-Ironman bike leg may aim for approximately 210 grams of carbohydrate across the ride. This can come from gels, energy bars, sports drinks and other suitable carbohydrate sources.

Carbohydrate requirements may be slightly lower during the run. The same athlete, for example, may find that 40–50 grams per hour works well. Your own tolerance and experience should always guide your final race nutrition plan.

Nutrition in the Days Before Your Race

In the three days before your race, focus on consuming adequate carbohydrates and fluids. Breakfast may include foods such as cereals that are not excessively refined or high in sugar, along with fruit and plenty of fluids.

Lunch and dinner should also include carbohydrate-rich foods together with moderate amounts of protein. Suitable choices may include pasta, rice, vegetables and lean meats such as chicken or fish. Avoid unfamiliar foods, excessive fast food and highly processed meals.

Hydration Before Your Triathlon

Keep your diet familiar and avoid introducing foods your body is not used to. Drink adequate water and include electrolytes where appropriate in the days leading into the event, particularly the day before the race.

Your largest meal on the day before the race is generally better consumed earlier in the day or around lunchtime. You can then graze through the afternoon and still have dinner without overeating late in the evening.

Race Morning Triathlon Nutrition Advice

Your race-morning meal should ideally be consumed around three hours before the start. Choose familiar carbohydrate-rich foods that you know digest well. Examples may include cooked oats, toast with banana, jam or honey, together with an appropriate carbohydrate drink.

A commonly used target for the pre-race meal is around 2.5–3 grams of carbohydrate per kilogram of body weight. However, this should be practised in training rather than tried for the first time on race morning.

Avoid overloading on simple sugars immediately before the race. Instead, include more complex carbohydrate sources that provide a steadier release of energy. Continue drinking water as needed until approximately 30 minutes before the start. If it is part of your tested strategy, you may also consider an energy gel around 20–25 minutes before the swim.

Race Day Fuelling and Hydration

If you experience stomach discomfort during the race, temporarily switching back to water may help dilute the concentration of carbohydrate in your stomach. Once things settle, gradually resume your planned calorie intake.

Remember to take in water as well as sports drink. Combining large amounts of carbohydrate drink and gels without adequate fluid may create an overly concentrated mixture in the gut.

For long-course triathlon, it is generally easier to consume more of your nutrition on the bike than on the run. Digestion is usually more comfortable while cycling, and the bike leg gives you a good opportunity to stay ahead of your fuelling requirements.

During the final 20 minutes of the bike, continue drinking without overdoing it. Once you have settled into the run, you may take a gel within the first few kilometres if that matches your tested strategy. From there, a gel approximately every 30–40 minutes may work for some athletes.

If you choose to use cola during the run, consider saving it for later in the race rather than relying on it early. As with all triathlon nutrition advice, the most important principle is to practise your entire fuelling strategy in training before race day.

For additional evidence-based sports nutrition information, visit the Australian Institute of Sport nutrition resources.

Want to Improve Your Triathlon Experience?

Want to improve? Find out more about how Multisport Consultants can help improve your race splits with a specific triathlon training program. If you feel you may benefit from a more personalised approach, contact Multisport Consultants for more details.