Free Ironman 70.3 training plans
Training > Long distance

Ironman race day: 10 common mistakes

Ironman racing is a long day and that means a lot can go wrong. But it doesn’t have to if you have a methodical approach. Phil Jarvis, head triathlon coach at, points out the pitfalls we all should avoid.

1.    Bad nutrition

The dreaded N word. When you’re racing sprint and standard distance, it’s straightforward, right? You top up your carb stores the night before and then maybe a gel or two to see you through. But Ironman can be up to 17 hours of consistent effort and no matter how adapted you are to using fat as fuel, you are going to need to replenish. Many a personal best has been derailed by squatting in a portable toilet when you should be eating up the course, but when the body is under duress, digesting the calories is often not straightforward. The best approach is to turn up at the start having eaten heartily (but sensibly) in the days before the race, then breakfast around three hours before.

Ironman nutrition: plan for success and nail the fuelling

This will top up your glycogen (energy) stores for the race. Whether you choose to go for gloopy gels or jam sandwiches, judging the quantity is important. Over-eating will be uncomfortable and bring on GI distress, under-eat and you’ll slow down, or ‘bonk’. Researching the provision of on-course nutrition is advisable, even if you plan to fuel yourself, because many a bento box has been spilled from the bicycle to the tarmac. It also pays to practice on longer training rides and runs with what you will use on race-day itself. As for hydration, drink to thirst. The biggest danger is drinking too much water. This is serious because with your body’s essential minerals diluted there is a real risk of hyponatremia, which can lead to a coma and death in extreme cases. Post-race, don’t head straight for the beer tent. Make sure that tummy is settled first. Sip rather than gulp and you’ll enjoy the celebrations a whole lot more.

Hydration: 5 mistakes triathletes make and how to avoid them

2.  No research

One of the simplest tasks, yet it is remarkable how many athletes arrive at the start having no concept of the challenge they are to undertake. Some might argue that a step into the unknown is preferable to being scared witless by the 140.6 miles to come, but that’s not the approach, we’d recommend.

Ironman-distance triathlons: the 10 best European Irons for beginners


Remember the five Ps: perfect planning prevents poor performance, and set aside time to assess the course and conditions, ideally before you enter, certainly when it comes to training and most importantly of all, before race day itself. Common mistakes include not checking the profile or terrain. If it’s a hilly bike course, you need to be prepared to climb – and descend. If the run is on boggy trail, then you’ll come unstuck with your racing flats. And finally, make sure you read the pre-race instructions fully and don’t miss the race briefing. They are ‘mandatory’ for a reason. Every event has its own little quirks and often there can be unforeseen, last-minute course changes that could impact your race.

Continue reading our guide to 10 common Ironman race day mistakes (2/4, faults 3-5)


Phil Jarvis is head triathlon coach at


Daily deals from top retailers

We'd love you to add a comment! Please login or take half a minute to register as a free member

Back to the top