Nutrition for a 70.3 Ironman: A Complete Guide

What Is an Ironman 70.3?

An Ironman 70.3, often referred to as a “Half Ironman,” is a middle-distance triathlon that challenges both your endurance and strategy. 

A 70.3 Ironman (Half Ironman) is a challenging endurance race, typically taking between 4.5 and 7 hours to complete. Your nutrition strategy is crucial to sustaining energy and avoiding fatigue. Let’s break down the essentials to ensure your nutrition plan is dialed in.

1. What Should You Consume During the Race?

Your body needs calories after about 75–90 minutes of exercise. For a 70.3, this means you’ll need to consume energy consistently throughout the race. There are two primary approaches to race nutrition:

Carbohydrate (CHO) Based Nutrition:

  • The body can only store enough glycogen (CHO) to fuel 60–90 minutes of exercise. For longer races like a 70.3, you’ll need to replenish these stores.
  • Common options include:
    • PB&J sandwiches
    • Bananas
    • Liquid calories (e.g., sports drinks like EFS Pro from First Endurance or other carbohydrate drinks)
    • Snacks like Fritos, beef jerky, or even breakfast tacos!
  • Experiment with different foods during training to find what works best for you.

Fat Utilization:

  • Some athletes train their bodies to rely more on fat as fuel. This approach often involves using products like Generation UCAN.
  • If you’re interested in this strategy, consult a coach or sports nutritionist, as it requires specific training and dietary adjustments.

2. When Should You Take Nutrition?

Pre-Swim:

  • Eat a small, easily digestible snack 30–45 minutes before your swim, such as a banana or a gel.
  • Avoid trying anything new on race day to prevent stomach issues.

During the Bike:

  • The bike leg is the best time to consume the bulk of your calories.
  • Aim for 240–300 calories per hour, depending on your weight and energy needs. Adjust based on what works during training.
  • Set a timer (e.g., every 15 minutes) to remind yourself to eat, drink, or take supplements.
  • Vary your nutrition between solids, liquids, or gels to avoid flavor fatigue.

During the Run:

  • Take in smaller amounts of nutrition on the run, as the body is less efficient at digesting during high-impact activities.
  • Example: Use a product like EFS Liquid Shot (400 calories per bottle) and consume a small portion every 3 miles.
  • Remember, it takes about 15 minutes for nutrition to be absorbed, so plan accordingly.

3. Hydration and the 70.3 Ironman

  • Drink to thirst: Overhydrating can lead to hyponatremia (low sodium levels). Listen to your body’s signals.
  • Factors like temperature, humidity, and your sweat rate will influence how much water you need.
  • For additional insights, consider reading research by Timothy Noakes on hydration and endurance athletes.

 

4. Practice and Personalization Are Key

  • Your nutrition plan must be tailored to your unique needs. Practice your race-day nutrition during long training sessions to identify what works for your body.
  • Avoid copying someone else’s plan—what works for a pro or a friend may not work for you.

Final Thoughts

A well-thought-out nutrition plan can make or break your 70.3 experience. Keep it simple, test your strategy during training, and trust your body on race day. By dialing in your nutrition, you’ll give yourself the best chance to perform at your peak.

Looking for more? Stay tuned for our guide on Ironman Distance Nutrition!