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.

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 practise 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.

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.

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.

3.    Wrong race kit

Pack and wear the correct kit, and you’ll not give it a second thought, make a bad choice and it could jeopardise your race and even be a serious health risk.

The key here is to take note of the race conditions and your goals and plan accordingly. For Ironman the key focus should be comfort. It’s all very well wearing that shiny new aero helmet, but if it’s a hot day those extra few seconds saved through lowered wind resistance will be nothing compared to the time lost as you over heat.

Go through your race step-by-step. Is your wetsuit suitable for the swim, will you need a thicker neoprene cap?

On to the bike, will you be content in a tri-suit for 112 miles, or would padded cycling shorts work better? Layering can be your chief weapon here. You may be cold on exiting the water in the early morning, but warm up through the day.

Once into T2, dress appropriately for running a marathon, and importantly make sure you have comfortable footwear. The best way to make sure you don’t miss anything is to follow our checklist (here) – and check the weather forecast!

4.    Avoidable mechanicals

You’re putting your mind, body and brake cables through intense strain – so don’t forget about the latter. There are few ways more frustrating to DNF in Ironman than suffering a mechanical, especially if it could be prevented by a quick bike check before the off.

It not only lessens the risk of a chain snapping, brakes rubbing or aerobars coming loose, it also gives you peace of mind in an unnaturally tense environment in the build-up. Even if you think your bike is in tip-top condition, it’s worth double-checking – saving a few watts of power through a properly lubricated chain equates to big gains over the long distance.

If you forget to check beforehand, there is usually a mechanic on site for last minute help. Finally, a common problem is either loose or completely incompatible cleats on bike shoes. It’ll be a painful pedal mashing experience if you cannot clip in.

5.    Not having a Plan B

The one thing that can almost be guaranteed in Ironman is that the race will not run smoothly. From a mass swim start to running down the finish chute, there are a myriad of things that can go wrong. Staying positive is critical, but also think ‘What would I do if…’ and run through potential scenarios.

Can you swim if you lose your goggles? Could you cope if the swim is ruled non-wetsuit? Can you change a puncture? Can you change a puncture when you are shivering and cold on the roadside? Do you have a strategy to switch to run-walk, or even start the marathon with run-walk, depending how you feel alighting the bike?

Setting different goals is also helpful. If you only have a ambitious A goal and your time splits start to slip, your mind-set needs to be correct to salvage the race. It’s easy to see those without a contingency plan. They’ll be walking the last half of the marathon.

6.    Smashing it from the off

Being able to mete out your effort in an efficient manner is one of the most difficult challenges in Ironman. Unless you’re at the sharp end where race tactics might dictate, your fastest time will arise from an even distribution of intensity throughout the day. Sounds easy, tough in practice.

The swim being ‘only’ 2.4 miles is perhaps the easiest to pace properly, and is also the one discipline where it may pay to go out hard (for the first 100 strokes or so) to secure a decent position in the field. Once settled in, good sighting to take the shortest line and not kicking excessively will help save energy as you head for T1. On the bike the old Ironman adage of ‘If you think you are going too slow, slow down’ is probably true.

If you ride to feel, you should have good idea of how fast you can go from your training. If you find yourself eating up the course 5mph faster than you’re used to, expect it to be paid back with interest on the run.  The marathon is where the wheels typically come off. Being able to run a perfectly paced marathon is the holy grail in Ironman.

Your training, and long brick sessions (long bike to long run) should help you with this. You might need to park your ego and opt for a walk-run strategy – eg 9mins run, 1min walk, or walk the aid stations, to keep you in check through the early miles and give you a much needed breather late on.

Rest assured, if you’re losing a few seconds per mile from your target pace early in the marathon, it will be nothing compared to the time you haemorrhage in the latter part should you set off too quickly.

7.    Poor bike set-up

Worth a category on its own purely because you spend so long in the saddle it can make or break your race. If you step off into T2 and feel as if you’ve two iron rods in your lower back, it’s going to be a painful shuffle. Many age-groupers already have tight hamstrings or hip flexors and running and biking only exacerbates the problem, tilting the pelvis and putting strain on the lower back.

On race day, you need to be comfortable, pure and simple. Sure, you could have what looks like the perfect aggressive aero position, but if you cannot hold it for more than half the bike ride and have to constantly sit up to stretch, then any gains from reduced wind resistance will be quickly lost.

A good bike fitter can help, and once you have the position set up, make sure you practice. (A note of caution. If you are using clip-on aerobars on a road bike, the set-up needs to be suitable If you are just fitted to the drops, you’ll be stretching out further for the clip-ons.)

 8.    Minor irritations become major issues

You might be able to get away with it in shorter races, but not addressing minor issues can lead to major problems in Ironman. If you’re prone to wetsuit rub, making sure you’re lubricated around the neck is vital. Due to hours of run and bike training many age-groupers suffer with tight hip flexors and hamstrings.

If you don’t take time to stretch on the bike – getting out of the saddle once in a while – you may find the first few miles of the marathon particularly painful. Likewise, look after your undercarriage with the right application of cream. If you’re not changing into bike short, 112 miles can be quite a toll in an underpadded trisuit.

When you start on the run, the nipples, under arms and inner thigh can all chafe and make the marathon a miserable experience.  The same is true with sunburn, not just uncomfortable, but providing long term health risks. So keep slapping on the sunscreen.

Not taking care of the small details is not only detrimental to physical performance, but the mental side too. As many know, Ironman is about being right mentally as much as physically, so and the last thing you want to be plagued by is a horrible blister because you’ve neglected your feet.

9.    Being late to the party

Given you’ll have trained for months paid a hefty entry fee and probably bought a fair bit of new kit, you’re jeopardising quite an investment if you risk leaving everything to the last minute. Arriving too late at the venue can be a recipe for disaster.

We’re not asking you to acclimatise for three weeks, but being able to familiarise yourself with the course and conditions, and importantly where you need to be and how much time you need to leave to travel to the venue on race-day morning (in the dark) is critical. Arriving early also means that your stress levels – which will be naturally elevated – will have a chance to settle.

Often, it’s not just the athlete you need to consider. If you have friends and family travelling to support, where and how will they be catered for. If you think they cannot cheer you on in relaxed confines, it’ll play on your mind and you can lose focus on the race.

10. Forgetting to say thanks

Last but by no means least, don’t forget to say a big thank you to as many people as possible. That includes the race volunteers and those who have helped get you to the start line. Ironman might be a long solo day, but it’s the support network that helps you through, so however grumpy you feel because you’ve missed your target time, or chowed down too many energy gels, remember these loyal folk and they’ll stay with you every step of the way.