Race Day Execution Mistakes: Lessons from 19 Iron-Distance Battles

Between 1995 and 2017, I toed the line at 19 Iron-distance races. Nineteen times I stood on that start line, nerves jangling, wetsuit zipped, heart pounding. Nineteen times I swore I’d learned from the last one, and nineteen times I discovered that Ironman has a way of humbling even the best-prepared athlete.

Last week, I shared some of the training mistakes I made along the way. (You can read the article HERE) This week, I want to talk about the ones that happened on race day itself, the moments that cost me time, comfort, and sometimes my enjoyment of the sport I love.

If you’ve been there, you’ll probably recognise a few of these. And if you’re still on your way to your first Iron-distance race, maybe you can sidestep some of the pitfalls that took me years to figure out.

1. Using the same nutrition plan for every race

For far too long, I believed that once I’d found a nutrition strategy that worked, I could just repeat it. In my head, I’d “cracked it”, the magic combination of gels, bars, and fluids that got me through one Ironman would surely get me through the next.

But here’s the truth: no two races are the same.

Your goals change. The terrain changes. The climate changes. Even your body composition and sweat rate can change. Yet I stubbornly stuck to a single plan regardless of conditions. The result? In about three-quarters of my races, I was vomiting on the run. Not ideal when you’ve still got a marathon to cover.

Check out this race day nutrition/hydration podcast

Looking back, it’s obvious. Hot races require more fluids and electrolytes. Cold ones demand different fuelling timing. A hilly course burns energy differently to a flat one. And your stomach can handle different foods at different intensities.

Nutrition is not a fixed formula, it’s a living, breathing part of your race strategy. It must adapt to the day, the conditions, and how you’re feeling.

2. Riding too hard and paying for it on the run

“If it feels just right, it’s probably too hard. If it feels too easy, it’s probably the right pace.”

Those are words I used to share with athletes I coached. The problem? I didn’t always listen to them myself.

Like so many triathletes, I loved the bike leg. It’s easy to get carried away, chasing average speed, pushing the power a bit more than you should, convincing yourself that the stronger you ride, the more time you’ll have in the bank for the run.

The flaw in that logic is simple: there’s no such thing as “time in the bank” in Ironman. You pay it all back with interest when you hit the marathon.

For years, I entered T2 thinking I’d got my bike pacing just right, but reality soon kicked in. It took me a long time to accept that finishing the bike feeling “too fresh” is exactly where you want to be.

On the few occasions I got that balance right, I ran strong, steady, and proud. And funnily enough, those were the races where I hit my best times.

One final story. As a coach I’ve heard two types of post-race summary. Which one would you prefer to be telling?
“I nailed the bike. My run sucked.” or “I had a great run. I thought I could have ridden harder.”

3. Listening to the wrong voices

Every athlete knows the mental battle that begins somewhere in the second half of the marathon.

There’s a devil on one shoulder whispering, “It’s OK to walk. You’ve done enough.” And an angel on the other saying, “Keep running. You’ve worked too hard to stop now.”

Too often, I listened to the wrong voice.

It wasn’t always because I was physically done, it was because I didn’t have a strategy for managing those moments. I’d let fatigue and doubt creep in, and once that first walk break happened, it was hard to start running again.

Looking back, those moments were less about fitness and more about mental preparation. The best athletes I’ve coached aren’t the ones who never hear those voices, they’re the ones who decide which voice gets the final say.

4. Not having a run/walk strategy

Running was always my weakest discipline. And yet, every race, I lined up with the same stubborn goal: to run the entire marathon.

I managed it twice.

For the rest, fatigue, heat, and nutrition issues took over, and I ended up walking anyway, but without any plan behind it. Each unplanned walk felt like failure, which made the next one easier to justify.

In hindsight, a structured run/walk (or what I now call “broken endurance”) approach would have been far better. Mentally, it’s easier to stay positive when walk breaks are planned rather than forced. Physically, it can make little difference to overall time, especially in long-distance events.

I’ve since seen plenty of athletes run their best Ironman marathons using deliberate walk intervals. They stay in control, stay fuelled, and finish stronger, both in body and spirit

5. Focusing on time rather than experience

For many of my races, I had a single goal: qualify for Kona. Everything revolved around that. The finish time, the age-group position, the splits, all of it mattered more than anything else.

But in the handful of races where I went in simply wanting to finish well, to soak up the atmosphere, appreciate the volunteers, and enjoy the day, I had a completely different experience.

Those were the races where I smiled, chatted, high-fived strangers, and remembered why I loved the sport.

It’s easy to forget that Ironman isn’t just a test, it’s a privilege. Very few people get to swim, bike, and run 140.6 miles in a single day. The medals and times fade, the memories last.

Final thoughts

Nineteen races taught me plenty, but perhaps the biggest lesson is this: experience doesn’t automatically make you wiser. You have to reflect, adapt, and keep learning.

Ironman rewards patience, humility, and awareness more than brute strength or stubbornness. Every mistake I made, from nutrition blunders to pacing errors to mental lapses, became part of the process that shaped me as both an athlete and a coach.

So as you prepare for your next race, remember, your real goal isn’t just to cross the line faster. It’s to finish better, smarter, calmer, and more present. Because that’s what being Battle Ready is all about.

👉👉👉 What's the biggest race day mistake you've made? I'd love to hear your story — these shared experiences help us all get stronger and smarter.

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