This is the part of your Ironman nutrition that requires the most planning. Not only do you need to think about how much you need to be fuelling yourself throughout the race, but you need to know when to re-fuel and how to do so during the three different events and transition periods.
How many calories should I eat during an Ironman?
During an Ironman, you will likely expend between 600 and 1,100 calories per hour, depending on your height, weight, body composition, fitness levels, metabolism etc. If it takes you 10 hours to complete the Ironman, you will expend between 6000 and 11,000 calories during the race! This doesn’t mean you need to consume this many calories during the event as your body will also use your existing fat stores for fuel (typically around 1750kcal to 2000kcal). However, it is critical that you eat enough calories during the Ironman so you have enough energy and are not in a significant deficit by the end.
With this in mind, you should be looking to consume at least 3000 calories during the Ironman. Generally, the more you can consume the better, as long as you can comfortably digest it.
What is the best nutrition for an Ironman race?
Although it’s important to be aware of your calorie intake during the Ironman race, you also need to be aware of the nutritional value of the food and drink you’re consuming. We strongly recommend bringing your own fuel, such as energy bars, sports gels and hydro tabs. This way you know exactly what you’re eating and you won’t need to deviate from your training nutrition.
If you are looking to take up the nutrition options available on the course, there are few more considerations you need to take into account:
- What is being provided along the course in feed stations?
- How often is it available?
- Do I get on with the nutrition provided on course?
Remember not all nutrition products are equal in nutritional content, so do your research before the race so you’re not faced with any surprises. Make sure your food sits well with your stomach, and that you are taking in enough carbohydrates and electrolytes (e.g. sodium, potassium, magnesium).
For example, the below is true when using OTE Sports products:
10 hours Ironman x 80g of carbs/hour= 800g
From consuming the above you will have taken on board just over 3000 kcal, your fat stores will also contribute around 1750kcal to this total.
Carbohydrates
During an Ironman, you want to aim to consume 60-90g of carbohydrates per hour. So, for a 10-hour Ironman, and an aim of 70g of carbohydrates per hour, you would need to consume 700g within the race.
Our body stores carbohydrates in our muscles and liver, but these stores are limited and get used up during exercise. When we run out of carbohydrates, we start to burn fat for energy. This might sound great, but when exercising at any sort of intensity, it isn’t beneficial. Without sufficient carbohydrate stores, the intensity we can perform at decreases dramatically. This is why one of the main aims during the event is to keep these stores topped up.
OTE’s Super Range has the perfect products to ensure you get in enough fuel for the entire Ironman race. The Super Carb Energy drinks contain 80g of carbs per serving and are available in two delicious flavours, Blackcurrant or Lemon & Lime. Alternatively, our popular Super Gels have 40g per serving.