Well where do we start with this one? It’s a very tricky one with so many variables…. what should people eat and drink and when.

In my experience over the years even most pros could not tell you what to do.  In fact I’ve been flabbergasted over the years on this topic.  I remember Macca in a mess his first 3 Konas I’m sure he won’t mind me saying, or Pete Jacobs had issues for years not wanting any fuel at all.

We can talk ketone diets, 40/30/30 diets, hi carb low carb oh the list goes on and on doesn’t it, so let’s try go back to the basic fundamentals.

We need hydration so we don’t dehydrate…..

We need fuel because our bodies stores cant cope through an event that long without it…



The first rule is if you just drink water you will end up flushing your salts away and ending up with same effects as dehydration in getting hyponytremia.  You need sodium potassium and magnesium at a minimum, which are your basic electrolytes.

There are many options for how you take these.  You can take it in drink powder, but I don’t know of any drink powder that has enough so you will need an additional supplement of salt tablets like hammer endurolytes, lava salts, salt stick capsules etc.  In general you would need one an hour on top of your drink powder (about 600mg of salt total an hour), if u sweat alot or its hot go for 900mg i.e. 2 tablets.

You can take electrolyte tablets that dissolve in drink like nuun, h5 zero, hammer fizz, power bar electrolytes etc but beware your gut can be affected by the sweeteners added.  Even stevia sweetener in GU and nuun can do that to your gut if it’s sensitive.  Stevia is a natural one but many others are not and even worse.

A very simple option would be to just use water and electrolyte pills if you’re very sensitive.

That’s the electrolyte side….. The drink side is you need in a race in general conditions a litre an hour.  Those that don’t will find your stomach will shrink and nothing will go in…. you will probably blame the gel, but it’s because you’re dehydrated.



This can be solid liquid or gel and the amount depends on the rate your body is using it and your size.  The problem here is the gut can not always take as much as you are using and this is the big problem.  In short distance races and in hi heart races you will burn it so fast it’s not funny and of course if we trained our muscles to go this fast over Ironman distance the fuel would not be able to keep up with how much energy or fuel used.  The gut can usually only take about 300 calories an hour or can be tricked by using fructose.  However, fructose can have massive stomach problems for some people.

This is exactly why we cannot do Ironman at Olympic pace the gut would not cope.

So typical problems come about for various reasons with fuel

  • The sweeteners in your fuel
  • Putting too much or too little fuel in
  • Too long gaps between fuels – try to nibble every 20 minutes
  • Too much sweet sugar
  • Caffeine can be a diuretic
  • Allergies of course

The best way is to try to start with a more natural product without the sweeteners and additives, research the ones that are the most natural and feed them in slowly.  Stick to your Ironman race pace and don’t scoop up your carbs before it can be replaced. At low heart rates you can burn more fats yes, but be careful as a race is a race and fat will not always be able to keep up with your energy needs.

In the old days bananas, figs dates almonds and walnuts did the job and very well but they are not as practical to take always.

There is no one answer for everyone….You need to try and test in training at race pace ,then at a race then take it into your Ironman race…good luck!