As Triathletes, we all know that triathlon training burns calories but when we embark on a really big training session, there can be anxiety as to what is the best thing to eat and how much. We want to make sure we can get through the session without having any nutrition related issues. The most common fear is that through poor nutrition we may run out of energy and this could compromise our workout, commonly known as the bonk (slang for running out of energy due to inadequate nutrition).

Triathletes are a meticulous bunch but nutrition is often one of the final pieces in the puzzle when it comes to optimising your performance. Triathletes are not totally focussed on body composition goals in the same way other athletes may be and because of the volume of training, many triathletes will think they can get away with poor nutrition choices, but the more savvy know too well that you can’t out-train a bad diet – poor nutrition will always harm your triathlon progress.

Optimal nutrition pre/during and post ride must be considered to ensure good performance during your training but also good recovery afterward so that you can hit your next Triathlon workout feeling good.

The fear of bonking can be our own worst enemy when it comes to good nutrition and diet. Most triathletes will over fuel and as a consequence, slowly begin to add body fat. This is partly down to the fact that when training you will likely be hooked up to some device that measures your calorie burn. This vast overestimation of calories burnt in training then leaves the Triathlete wondering whether they have eaten enough. The fact is that all devices overestimate, so when your watch tells you that 2000 calories have been burnt in two hours, this does NOT mean you need to eat those 2000 calories back – sadly the exact number is hard to know. But many Triathletes will use this as an excuse for poor nutrition aka eating crap!

Bonking though is a hideous experience. I have had two brushes with under fuelling in my life, both when I was much younger and dare I say more stupid/arrogant, cocky, or just didn’t know what I was doing. Once I had to be saved by a passing cyclist as I sat at the side of the road – he gave me some cash so I could buy something at a petrol station up the road – I am eternally grateful.

Most people though will not have under fuelled so they end up in such a state and in fact, as mentioned, already are more inclined to overdo the nutrition – aka eat too much.

To avoid this the best way is to know how many calories you consume day to day – essentially you learn how much fuel you need to put into the tank to fuel Triathlon specific training but also daily life. Then based on your training session you can make nutritional adjustments so as to ensure adequate fuelling. There are many formulas (check out my e-book here) that will help you guesstimate your daily calorie burn but really the only way of knowing is to test – This means weighing yourself and monitoring calories – if you are gaining weight you are eating too much – if you are losing weight you are not eating enough.

Once you know your calories, you can then begin to adjust the amounts you need each day. Many Triathletes will just eat the same most days but really a rest day or light day needs to be radically different from a long ride in terms of nutrition choices. For more on this check out the article on setting up a diet for Triathlon specific training.

One good rule of thumb is to deduct calories from your easiest day/rest day and add them to your longest/hardest day.

For example, if your calorie burn is 2500.

Deduct 500 from a rest day.

Add those 500 to your longest/hardest day.

This means you still come out at 2500 calories on average for the week.

How you add those calories in will depend on when you are riding.

Most people will do their longest ride at the weekend, so I will assume your last meal will be breakfast – this meal is the most important of your nutrition for that day.

Breakfast should include a decent amount of protein, carbohydrate, and fats. Good options are eggs on toast with a side of porridge (oatmeal) and some fruit. The number of calories you consume will differ on your size, goals, and length of the ride but it must be a bigger breakfast than a non-training or easier day – obvious I know but so many people don’t take this into account and think just swilling down a gel will do the trick, which is, to be honest, just lazy nutrition.

I should also warn against doing such rides fasted – whilst fasting is having its moment in the sun and you may think it is a good way of burning some fat, this is not a time to not eat breakfast.

In terms of in-ride nutrition, the most important thing is to know how much you have. So weigh things out before you go, know how many calories are in your food, and have a rough plan of when to eat it, this means eating when you are not hungry.

For example, measure out nuts, dried fruit, chocolate, broken up protein bars, and protein cookies and put it all in a bag. Have a handful every 30 minutes.

Have a sports drink which you sip on, continuously.

Have a gel or two for emergency use, but don’t use it unless you have to.

If then for example those calories add up to 750, you can track whether things are working – if you felt strong, stick to the nutrition plan. If weak, add in more next time, sadly this is about experimenting when you’re trying to figure out the best nutrition for yourself.

Before you leave, know exactly what you are going to consume when you get back and ideally have it made. Again measure everything so you know what you are getting. The best options for post-training are liquid, just because they absorb quickly for obvious reasons. My personal favourite is:

300ml full-fat milk

1 scoop chocolate protein powder

1 banana

1 teaspoon of cocoa

1 teaspoon honey

This is a protein and carb rich meal that is also very tasty and is something to look forward to.

As with all things triathlon nutrition-related, there is no shortcut (apart from getting nutrition coaching) you need to learn about yourself, maybe make some mistakes (not big ones), and figure out what works and in time you will have a bulletproof nutrition plan which works every time. This may seem like a lot of effort but it is worth it. You will be leaner, faster, healthier, and not have to worry about bonking – so get to it!