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Skratch Labs: Ironman Fueling Tips

Skratch Labs: Ironman Fueling Tips

Nutrition can be tricky and is highly individual when training for an Ironman event. Trial and error is key when it comes to dialing in your race day needs. Here are some tips to help!

There are 2 major things you need to plan for during your event —hydration and calories. Hydration will primarily come from electrolytes in drinks, like our Sport Hydration Drink Mix, and calories will come from the carbohydrates you eat in on-the-go food – unless you drink Superfuel.

As for the event itself, we like to think in terms of a timeline to help guide athletes. (The portions & products may vary for each athlete.)

Starting at 3-5 days before the event

  1. Start increasing carbohydrate intake. This may begin by looking like 5 g/kg of body weight and increase up to 10g/kg the night before the race. Taper so that your body can adjust to the influx of carbohydrates. You can typically start by replacing some of your snacks with higher carbohydrate sources or adding an extra roll or scoop of carbs at mealtime.
  2. You may see your weight go up during this time, but that is due to the increased glycogen in your body which will carry some water weight with it. It’s extremely normal to experience weight gain while for endurance events.
  3. While increasing your carbs, also be aware of your hydration. Aim to increase your hydration in the days leading up to your event — especially if you are traveling. When traveling, we tend to miss out on important hydration. Lack of humidity in airplanes can also lead to quicker dehydration.

The night before

  1. Eat a good dinner with at least 50% of your meal coming from carbohydrates. You want to be closer to 8-10g/kg of carbohydrates to prepare yourself for the event
  2. Pre-load your sodium. Use products like Skratch Hyper Hydration the night before or as Dr. Lim would recommend, try having a bowl of miso soup with your meal. This will aid in proper hydration and prepare you to prevent dehydration and sodium losses early on in your race.
  3. If you have a hard time eating in the morning before events, have a bedtime snack with a combination of carbs and protein. A glass of chocolate milk is one of our favorites, you can also use Skratch Recovery Mix!
  4. Get a good night of sleep! Rest can be one of the most important factors in being prepared and ready for a big event.

The morning of

  1. Start hydrating immediately when you wake up. Depending on your electrolyte needs either drink water, Sport Hydration Drink Mix, or Hyper Hydration Mix.
  2. Try to eat your breakfast 3-4 hours ahead of start time. If that is difficult for you due to an early start time, focus on a good bedtime snack and then have a high-carb breakfast 2 hours before your start time.3. At warmup/start (about 15-30 minutes before) top-off your carbohydrate stores. Use Skratch Crispies, Chews, Energy Bar, or Superfuel to get yourself prepared for the swim portion.


Fueling during the swim is not recommended. The breakfast you have that morning and topping-off before the swim are essential to get through the first portion!


  1. At T1make sure you have all your essentials. Fueling should start now. The bike portion of the Ironman is the make-or-break point for most athletes to know if they are on track with fueling. Try to consume any of your fuel that might be difficult to carry or eat at this time. Some people like PB&J, others like bars or rice cakes. Do what works for you! Just make sure you test it before the day of the race.2. Once on the bike, you will want to consume somewhere between 30-60g/hr of carbohydrates; some athletes can even push their intake upwards of 90g depending on their usage/GI tolerance. Use a combination of sports drinks (type varies based on electrolyte needs) and foods like Skratch Crispies, Bars, Chews, or Superfuel.3. Prioritize Hydration. If you are in a hot & humid environment you may need more hydration than you are used to. Practice hydrating in heat before your race. Some athletes will have up to 1L per hour of sports drink during their ride replacing at least 500-700mg of sodium per hour. Here is a video that shows how to concentrate your Skratch for your next Triathlon.


  1. A lot of the concepts from T1/Bike apply here. The main difference is that if you had a hard time fueling on the bike, you may feel it here during your run. Use T2 to your advantage and get your fuel in during this time. Once you start running the jostling of your intestines may make digestion harder, thus leading to some of the gut issues athletes endure in races.
  2. Stay on top of your hydration. Keep following your bike portion hydration plan. Stay the course with hydration!
  3. 30-60g/hr of fuel is ideal. If you are using gels, this would be the best time to use them as they can be tough on the gut. Make sure you are getting enough water with your gels if using them.
  4. Caffeine might be helpful here, do test caffeine prior to the event so you don’t upset your gut on race day. Caffeine may be helpful if you’re not feeling as energized or motivated near the end of the race.


  1. Prioritize recovery after your event… we promise you’ll thank us the next day!
  2. Get in some type of recovery nutrition immediately. We know how good that beer sounds, but a combination of carbohydrates and protein are much better. Timing is everything when it comes to recovery. We recommend replenishing at least 30-60 minutes after the end of an Ironman event. Our Recovery Mix is delicious and has the perfect 4:1 carbohydrate to protein ratio to make sure that you have everything you need to end your event with success!

A note about Superfuel: We usually recommend most athletes start at 3-4 scoops of Superfuel with 1 scoop of Hydration Mix (mixed in or in a separate bottle - up to you!) to make sure you have a balance of carbohydrates and electrolytes. For most females the serving sizes recommended is a bit too much and can be hard on our guts. We also recommend sipping it instead of trying to chug it all at once. If you need more guidance please let us know, but do try Superfuel before your event to make sure that you have the right proportions that work for you!

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