How to develop a race plan for Ironman – Hope Ain’t a Tactic

Ironman is a beast and demands a certain level of respect for the distance. It requires a level of dedication and time commitment that not many people can even fathom. Relying on hope when it comes to race day planning is not a tactic, and it’s not respecting the distance you’re about to tackle. But alas, this happens all too often. Athletes who have spent hours, weeks, months and personal sacrifices to make it to race day, only to have avoidable hurdles derail their race.

The reason Ironman is so tantalising and has many of us going back for more is this illusive quest for the perfect race. Does it exist? Yes, but rarely. And even in a perfect race, things may not go to plan but the difference is that you are able to respond to the adversity and carry on without hindrance.

When it comes to your own race planning, it’s important to control what is in your control. You can’t control the weather but you can control how you prepare for various conditions. You can’t control getting a flat tyre but you can control how you respond to fixing it.

When planning for an Ironman or long course race consider the following elements:

  • Pacing strategy and goals
  • Race day and race week nutrition and hydration strategy
  • Mental skills and psychology preparation
  • Logistics

In this article, I’m going to start with detailing how to plan your pacing and race goals, which will then determine your race day nutrition planning.

Pacing strategy and goals
The level of detail required for a pacing strategy will depend on experience and available data or technology. There is certainly a spectrum of approaches to take when developing a pace plan; it’s important for athletes to develop a plan that resonates with their personality style, with the goal to increase buy in, motivation and trust in the plan. With that in mind, following are a few different options to establish your race pace.

Step 1: Ideally ensure you (or your coach) have some threshold testing sessions scheduled in the final six weeks of your training program. We will utilise these sessions to gather your training data and make informed predictions.
Some examples of threshold
tests include:

Swim options;
a. 1km swim, in wetsuit, as a time trial threshold test
b. CSS protocol (see appendix)

Bike options;
a. Functional Threshold Power (FTP) Test [40-60 minutes]
b. Heart rate threshold test [40-60 minutes]
c. Laboratory based lactate threshold or Vo2 Max test

Run options:
a. Heart rate threshold test [40-60 minutes]
b. Laboratory (treadmill) based lactate threshold or Vo2 Max test
c. Aerobic pace test (MAF) as a run off the bike

BIKE ZONES: Calculate your zones via heart rate or speed/pace.


Step 2: Establish your threshold heart rate, pace and/or power output for
each discipline.

Next up is a guideline to work out your race heart rate, pace and/or power output for all three disciplines:

For an Ironman swim, you want your perceived effort to be four [Easy] – six [Moderate]. It should feel comfortable, similar to your “go all day” pace. Your breathing shouldn’t be labored, with the exception of the first ~400m where you will be putting in an effort to get clear water and a good drafting position. During this first stint, allow your perceived effort to push up to a seven or eight, but no higher.

Utilising your threshold test results, use an online calculator (I recommend TrainingPeaks) to calculate your zones. Your predicted Ironman race pace (per 100m) will fall within Zone 2/Aerobic. Then it’s up to you to practice this pace in training, ideally in the open water, ensuring this pace matches the planned perceived effort.

The swim might not win your day, but it can absolutely impact it negatively. Your goal for the swim should be shaped around expending as little energy as possible; this includes mental energy too.

Using Heart rate or speed
Utilising your field or laboratory test results, calculate your zones (again, I recommend TrainingPeaks). Your Ironman speed or heart rate will fall within Zone 2/Aerobic Endurance. If you are a first timer, you will want to plan for low zone two and if more advanced, you can aim for top of zone two, low zone three. Take note of your speed and heart rate ranges – see example above.

Using Power
Utilising a power meter is the most accurate way to plan for an Ironman, as it helps account for wind resistance, road surface, hills and declines*. Based on your FTP result, calculate your Ironman power based on the following guidelines: (See appendix for further resources)


I still recommend noting your heart rate for a given Ironman goal power output. We don’t want to be too singular in the data that we measure on race day because, firstly, anything is possible when it comes to technology breakdowns and secondly, it’s important to be fluid and responsive to multiple data sets on race day, rather than focusing on one number.
With that in mind, ensure your goal heart rate, power or speed goals utilise a range, as opposed to a specific single number. This sets you up for both physiological and psychological success. You will see this represented in the case studies over leaf.

If you’ve paced your swim and bike appropriately, (aka you followed the plan!) then your run-pacing plan should come together nicely.
Again, utilising the threshold data from your field or lab tests, calculate your run pace and/or heart rate zones. To establish an Ironman run pace, we aim for Zone 2/Aerobic Endurance. Let’s say you complete a field threshold test to establish your Zone 2 heart rate as 140-160bpm. To then accurately create a pace plan (especially for first timers) I recommend completing a MAF (Maximal Aerobic Function) test as a run off the bike. This would entail completing a long ride of ~5-6hours, and running 40-50minutes off the bike at a set heart rate. In this example the goal would be to sit as close 160bpm, without going over. Then we would look at your resulting pace for that heart rate to provide us with an approximate race pace and heart rate.


Race day nutrition strategy
Now that you have some goal times that are based on your current physiology we can now develop a nutrition plan that matches your goal pace and output.
If this isn’t your first Ironman, you will be able to develop a subsequent plan on what did and didn’t work for you last time. If you’re a first timer, you can base it off shorter distance races or the fuel that has worked well in training.

Here are some considerations when planning for Ironman nutrition:

  • The early start time – what time would you have to get up if you want to eat a breakfast prior?
  • Aid station locations – where are they and will you use them?
  • Special needs – where are they and will you use them?
  • Flavour fatigue – you might like the taste of your chosen sports drink over two hours, but how will you feel after 12-hours?
  • Gastrointestinal distress – the longer the race, the greater the risk of gut upset and subsequent toilet visits. Choose your fuel wisely and ensure you test planned volume in training.
  • Hunger – do you need to include solids in your nutrition plan?
  • Are you predominately a fat or carbohydrate burner at race pace/ intensity? This will dictate the volume or quantity you need for your given race pace.

How do you know if you are predominately a carbohydrate burner or fat burner? You might have an instinctive answer based on the number of times you visit bonk town and crave sugar or carbohydrates (a key indicator you are a sugar burner). If you are a trained fat burner, you will probably notice needing to carry less fuel than your comrades and cravings for all things sweet or starchy are pretty rare too.

As an endurance athlete, being a fat burner is what you want to work towards to give you a metabolic advantage. To determine if you are a sugar burner or fat burner, the most precise way, is to conduct a Metabolic Efficiency Test (MET). From this testing protocol you will have data to build an accurate nutritional plan, for both day-to-day (general) and race day (sports), which suits your personal physiology. An MET will establish your cross over point (COP), the point (heart rate or power output) at which you burn more carbo-hydrates than fats. This enables a plan that prevents bonking and allows you to express your full potential while also working towards optimal body composition and metabolic health in training.


Athlete 1 has been able to plan for less fuel due to their metabolic efficiency, whereby they are not burning a high level of carbohydrates at their given race heart rate. Their cross over point of 162bpm meaning they can work up to this heart rate without churning through an excessive amount of carbohydrates and prevent hitting the wall (metaphorically). If the race conditions on the day mean your heart rate is sitting higher than planned, then you would need to consume additional fuel from what was planned. This is why I also recommend carry spares! Athlete 1 has opted for solid food on the bike, as it’s their first Ironman and they don’t know if they will feel hungry or not.

Athlete 2 has more race experience, however their metabolism is geared towards burning more carbohydrates. Their COP is also much lower, and thus their race pace heart rate will involve burning a higher amount of carbohydrates. On average, Athlete 2 will need an additional sports gel per hour, when compared with Athlete 1; over ~12 hours, that’s 12 extra gels to carry. A great reminder, that becoming metabolically efficient in the pursuit of endurance sport is crucial to minimise logistics, gastrointestinal distress, risk of bonking, and additional stops at special needs or extra weight on the bike. Due to their experience, Athlete 2 opted for no solid food on the bike, as they have experience with this and know it works for them on race day. Athlete 2 has also accounted for their high sweat rate with increased electrolyte needs and additional salt in their liquids.

To establish these numbers and data points, refer to Part 1 of this article for pacing, but you might also want to investigate some laboratory testing to establish your cross over point and
sweat concentration.

To summarise, successfully planning for an Ironman you need to firstly respect the distance and do your due diligence when it comes to being prepared. This will avoid unnecessary stress or potential disappointment. Remember that you are a unique individual, with your own needs. Focus on what is right for you when it comes to how you plan your pacing and nutrition. This goes for your individual physiologically just as much as your psychology.



Images: Korupt Vision


Katee Gray

Katee is a self confessed “Hormone Nerd” with a background in Exercise Science and a passion for Triathlon. She combines her knowledge or physiology, functional anatomy, and testing protocols from her Bachelor of Exercise Science with research from fields of hormonal balance, female reproduction systems and triathlon related studies specific to females to coach and guide endurance athletes, which ultimately led her to penning her book: “Healing The Grumpy Athlete” - Embrace your Hormones and Achieve your Athletic Potential.
For more information check out
Facebook: @Holisticendurance
Twitter: @KateePeds

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