How to prepare for a non-wetsuit Ironman swim leg

With the hot summer we are all experiencing there is a higher chance that the race you have entered could actually be declared a ‘non wetsuit swim’. For some athletes this possibility can send shivers down the spine! But it shouldn’t says coach Matt Sanderson of Here he explains how to prepare

Credit: Getty Images Sport

The athletes most likely to worry about swimming without a wetsuit are generally the slower swimmers or those who got into triathlon without a background in swimming. The neoprene offers more buoyancy to the weaker swimmer and reduces the ‘sinky legs’ and improves alignment in the water. However, these same triathletes have been training for an Ironman for many weeks and months so physically you are fit and able to exercise for countless hours!


The swim might take a few minutes longer and it might feel a little slower but after the first 400 metres you will start to relax and forget that you don’t have the wetsuit on! The key points for age group triathletes not wearing a wetsuit are:

1 Practise in open water with and without your wetsuit. Start in your wetsuit and practise your transition by running out of the water and removing the wetsuit. Take a few minutes to recovery and then re-enter the water without your wetsuit on. It will feel different but after a few minutes you will adapt to the reduced buoyancy.

2. Stay relaxed! To swim efficiently we need to feel relaxed. Tension can inhibit the stroke mechanics and increase heart rate. Take a few moments before your swim to take some deep breaths and visualise what you are about to do. For me I try to imagine swimming in an alpine lake on my own with the sun shining down. My visualisation is from above and the stroke looks smooth, relaxed and effortless…. in real life it may not be but it gets my brain in gear!

3. Don’t swim harder trying to make up for not having a wetsuit on. Swimming harder uses more energy and commonly creates more drag which actually slows the swim down! Stay relaxed and ‘feel’ for a comfortable, efficient swim as you would have done in your wetsuit.

4. For the ‘sinky leg’ swimmers focus on your breathing. Avoid holding your breath as this lifts the chest in the water and sinks the legs. Instead, focus on exhaling into the water straight after the breathing stroke. The exhale should be constant and relaxed and in doing this will set you up to be able to inhale on the next breathing stroke and prevent a ‘gasp’ for air and over rotation.

And remember, you will save time in T1 trying to get out of your wetsuit if the water temperature is above 24.5 degrees!

Enjoy the experience and remember; it’s the same for everyone!”

Matt Sanderson is a BTF Level 3 coach and has qualified for the IM 70.3 World Championships three times. Find out more about him at

How to train for your first Ironman


How to race your first Ironman