Triathlons are gaining more and more popularity in recent years, attracting both novice and elite athletes worldwide to challenge themselves through the three domains of swimming, cycling, and running.

To fuel the hundreds of hours of training required to compete in these events, triathlete nutrition is paramount to success in one of the toughest and most rewarding endurance sports out there.

This article will lay the foundation of everything you might want to consider when creating your triathlon diet plan.

The Starting Line

The first thing to consider is your body composition.

Your weight and the distribution of fat to lean mass you carry will have a significant influence on your speed, endurance, strength, and the repetitive forces traveling through your joints.

So the first step to improving your race time and performance (and decreasing your risk of injury) is to determine your optimal weight and body composition, and adjust your calorie intake accordingly.

Triathlon Master

The next element that will affect your nutritional needs for a triathlon is your age.

If you are an older athlete looking to compete at the masters level, be aware.

The present data suggests that masters athletes consume significantly less protein (relative to body mass) and significantly less post-exercise carbohydrates than younger athletes.

This issue is a concern for any age group as it could impair your recovery, a critical factor in the triathlon game.

Pick Your Poison

Another crucial consideration before we delve into training nutrition is: for which triathlon event are you training?

The nutritional considerations for a typical 1-hour 45-minute sprint triathlon are vastly different to those for a 70.3 half ironman (on average, say, a 6-hour event).

The longer your race, particularly if you’re heading over the 90-minute mark, the more that eating while competing becomes a necessity to keep your tank from drying up.

The Motto

The American College of Sports Medicine and The Academy of Nutrition and Dietetics have a position statement on nutrition for athletes, from which you can apply the general principles to triathlon diets.

Their message is this:

Your performance and recovery rely on the optimal type, amount, and timing of the foods, fluids, and supplements you consume.

Remember, the following is a general guide only. Your specific needs will depend on many factors.

Although you can do your research and experiment with what works best for your body, getting professional advice from a qualified dietician is highly recommended to determine the best solutions for your situation.

Training Day

To compete in a triathlon at any level requires dedicated daily training.

You can expect to be clocking in up to 20 hours a week, with multiple sessions a day to train for the specific stages.

That’s a lot of mileage, and you’ll need to keep yourself fuelled and fresh if you want to avoid overtraining and burnout.

It’s All About the Macronutrients

Carbohydrates to fuel energy

Carbs are your fuel, and the amount of fuel you need will depend on your training goals, where you are in your competitive calendar and training cycle, and your total energy requirements and body composition goals.

Daily recommendations can range anywhere from 3-12 grams per kilogram of bodyweight depending on these factors.

Generally speaking, you’ll benefit from getting your carbohydrates from whole food sources such as grains, fruits, and vegetables.

Protein in high quality

During all that training, you’re going to need protein support to adapt, repair, and remodel your body metabolically.

While training for your triathlon, your daily protein requirements will generally range from 1.2 - 2 g/kg.

Your protein intake should be spread across the day and following intense training sessions, and ideally come from lean, high-quality sources such as lean meats, poultry, fish, and low-fat dairy products.

Fats - nuts, seeds and fish

Fats have many important functions within an athlete’s body, such as insulation, protection, and supporting a healthy nervous system.

You typically measure fat intake as a percentage of around 20-35% of total dietary intake, with 10% or less being the ideal amount for saturated fats.

Examples of optimal fat sources for gaining the most benefits to your training without the detrimental effects of overconsumption include nuts, seeds, avocado, and fatty fish oils.

In addition to these macronutrients that make up the foundation of a triathlete’s nutrition, there are several additional critical factors such as hydration, micronutrients, and supplements, which we will address in the following sections.

Race Week

So, you’ve made it through the months of hard work to get yourself race-ready.

Now we need to focus on carbohydrates, hydration, and any additional supplements in the lead-up to the race and for longer triathlons, nutritional requirements during the event to keep you performing at optimal capacity until you charge over the finish line.

Load Up

In the 1-2 days before your event, ‘carb-loading’ is a commonly used strategy to ensure your energy stores are completely topped up.

The guidelines are approximately 10-12 g/kg per 24 hours preceding race day.

Experiment with which types of foods allow you to achieve this intake without causing excessive discomfort.

On race day, you should consume an additional 1-4 g/kg of carbohydrates 1-4 hours before the start for pre-event fuelling.

Make sure you avoid foods high in fiber, protein, and fats to stave off gastrointestinal issues during the race, such as stomach ache, nausea, cramps, or worse.

Ready, Set, Go!

Every triathlon, regardless of distance, will progress from the swim leg, to the bike, and finish with the run.

Each phase has its special considerations for nutrition.

For the swim, the aforementioned pre-event meal should be sufficient to ensure you’re starting the race with a full tank, while giving your body 1-4 hours to digest and absorb the nutrients.

Once you’ve transitioned and settled in on the bike, experiment with hydrating first, then starting to consume your carbohydrates about 20 minutes into the ride.

Calories and caffeine consumption on the bike have been highly correlated with improved performance and lower overall finish time.

This leg is your best opportunity to consume your sports drinks and carbohydrate-rich snacks in small increments to set the stage for (and minimize interruption to) the run.

Last Legs

Finally, during the run, try to keep up with your hydration in small amounts at frequent intervals, with sports drinks and energy gels taken with water to get across the finish line.

If your event is under 2.5 hours, aim for 30-60g of carbs per hour. For ultra-endurance races, you can move that up to 90g/h.

Special Considerations

There are a few other elements to a triathlete’s nutrition that need mentioning here. First, micronutrients such as iron, vitamin D, and calcium play vital roles in training and recovery.

Second, the use of supplements, including creatine, caffeine, and beta-alanine, is a personal choice and should be researched properly before use.

Finally, don’t forget that like training, your diet and hydration needs will change depending on your climate.

Let us know your favorite nutrition tricks for a triathlon in the comments below!