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Brownlee brothers on the costly race day swim mistakes to avoid – plus their own mishaps

The swim might be the shortest part of a triathlon, but getting it wrong can put a stop on nailing that PR you’ve been training for. Age group long course triathlete Jenny Lucas-Hill, who has a bit of a ‘swim-cident’ track record, gets some top tips from Alistair and Jonny Brownlee on the most common race day swim mistakes – and how to avoid them. Plus they share their own swim mishaps, proving that even the PROs can get it wrong from time to time.
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I’ve made plenty of triathlon swim mistakes in my time. From my first ever open water swim, when I learned the importance of sighting the hard way by swimming face first into a giant inflatable buoy. To my first IRONMAN race, when I entered the water at Copenhagen’s Amager Strandpark and started swimming with gusto towards what I thought was the first turn buoy. Only for the ‘canoe of shame’ to glide over and let me know that I was actually swimming in entirely the wrong direction. Since then I’ve apparently not learned my lesson and had plenty of ‘swim-cidents’, ranging from the mildly embarrassing to the race ruining.

While the swim is only a very short part of a triathlon, it’s actually an area where plenty of us age group triathletes tend to give away a lot of unnecessary time. From pacing to navigational errors, race day swim mistakes can be costly and leave you either missing the front pack in short course, draft legal racing. Or dealing with a far more congested bike course in longer, non-draft events.

I caught up with Alistair and Jonny Brownlee to get their insights on the most common swim mistakes in triathlon – and how to avoid them. Plus, they shared their own ‘swim-cidents’ – because sometimes even the top PROs can get it wrong.

Throwing away technique

Ever exited the water in a triathlon feeling like you’ve really pushed your limits, only to glance down at your watch and notice your pace hasn’t lived up to the perceived effort? You’re not alone. “I think a big mistake people make in the swim is to throw their arms around too much and forget about concentrating on technique and holding the water,” says Jonny Brownlee.

“When you are fresh and the adrenaline is pumping, it’s so easy to just throw your arms over too fast with bad technique. But swimming is about easy speed. Try to swim the first minute of your race thinking ‘relaxed but fast’. I tell myself that I will take the first 10 strokes ‘big but relaxed’ – and then go from there.”

Going off too hard, especially if you’re not swimming efficiently, will leave you feeling exhausted and can have an impact on your bike and run. Try to stay calm and focus on pulling efficiently through the water. You could end up with a faster swim split, for less effort.

Aiming for the wrong buoy at the start

That little navigational issue I mentioned earlier that I had at IRONMAN Copenhagen? Turns out I’m not alone with swimming off in the wrong direction at the start. “I have started a race, dived into the water and aimed for the wrong buoy before,” Jonny shares. “You might think you know where you are going, but at race speed and with all the splash around you – it looks different. So make sure you really know where the first buoy is before you start.”

Generic triathlon open water swim photo credit British Triathlon
In the excitement of the race start, make sure you’re definitely swimming towards the correct buoy [Photo credit: British Triathlon]

If you have the opportunity, it’s always worth going to the practice swim before race day to recce the course. Practice your sighting in training – both in the pool and in open water – so that you can double check you’re swimming in the right direction without losing too much pace.

Leaving it until the last minute to check your swim gear

If it’s your first race of the season – or your first triathlon full stop – make sure you’ve tried all your swim gear out before race morning. “Another big mistake people make is to not try your wetsuit and goggles out before race day,” Jonny says. “Make sure you’ve tried your wetsuit on – and swam in it – before your race. And don’t forget to test your goggles out to make sure they fit comfortably and don’t leak.”

For experienced triathletes, nothing is going to add stress to race morning like putting your wetsuit on and discovering you’ve got a big rip in it after last season. And for beginners, swimming in a wetsuit can feel a little strange to begin with so you’ll want to make sure you’re familiar with it. Even if you’ve been using your goggles in the pool throughout your training. It’s worth testing them out in open water to make sure you can still see with any glare from the sun. You might need to opt for a pair with a darker tint, or a wider lens so you can sight properly.

Swimming off course

“The biggest mistake I’ve made was missing a buoy,” says Alistair Brownlee. “It was at a race in Australia with a massive current. I got to the first buoy and got pushed under by other athletes. I was under the water for what felt like a long time! When I came up I was on the other side of the buoy and carried on swimming. It turned out I’d accidentally gone around the inside and not the outside. So a very obvious mistake to avoid – make sure you don’t cut the course, even if it’s unintentional!”

Challenge Barcelona 2023 - Photo Credit: Jose Luis Hourcade
If things get congested a turn buoy, take a moment to make sure you haven’t accidentally taken the wrong line. [Photo: Challenge Barcelona]

Once you’ve made it to the first buoy at the start, don’t forget to keep checking you’re swimming in the correct direction. Swimming off course can add unnecessary extra distance to your race. Or, as Alistair has shared, if you accidentally cut some of the course out – you could end up with a time penalty. If the water is choppy, you’re in the midst of a congested pack of swimmers or you find yourself getting disoriented. It’s worth just taking that extra moment to get your bearings to avoid losing even more time with a costly navigational mistake.


Alistair and Jonny’s own swim mistakes are proof that even the best in the sport can get it wrong on race day! But take their training tips on board, use your pool sessions to hone your open water technique, and you’ll set yourself up for a strong swim split at your next triathlon.

Jenny Lucas-Hill
Written by
Jenny Lucas-Hill
Jenny Lucas-Hill is Content Director at TRI247. A five-time Ironman finisher, she's also a qualified personal trainer and sports massage therapist.
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