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Chrissie Wellington: how to increase swim speed and endurance for Ironman

Four-time Ironman world champion Chrissie Wellington offers six key tips on how to build up your swim to an Ironman-distance 3.8km…

Chrissie Wellington swimming (Image by Jonny Gawler)

Are you targeting your first Ironman this season but worried about whether you’ll be able to finish the swim? Four-time Ironman world champion Chrissie Wellington offers the following advice…

Acquiring the art of swimming isn’t easy, but nor is it rocket science. Many triathletes are non/weak swimmers initially and have overcome their fears to develop their skill, strength and speed at this discipline. Take pride in how far you’ve already come.

As a beginner swimmer, initially focus on trying to master the art and ease of swimming – that is, being able to cover the distance comfortably, confidently and efficiently, rather than focusing on speed. So the aim for you is to exit the water less fatigued and with more energy for the bike and run.

Remember: we are not swimmers, cyclists or runners… We are triathletes, doing one sport, not three, and each discipline affects the other. A consistent output over the entire race is what matters. So, for now, focus less on getting fast and more on enjoying the swim and feeling fresh at the end of the 3.8km plunge.

If you simply do km after km of drills, you may improve your stroke, but you won’t complete the distance. Focusing on acquiring fitness by building volume to the detriment of technique will make your efficiency slump. If you lack composure, you may panic, which will greatly affect your performance. Your training should simultaneously build fitness/stamina, good technique and confidence in the tri stroke of choice – front crawl.

Tip 1: Relax

Swimming requires relaxation, not rigidity. Take time to play around: splash, breathe, close your eyes, lie on the bottom, float, blow bubbles, go limp, do roly polys! Learn to feel – not fight – the water.

Tip 2: Breathe

When swimming front crawl, steadily and consistently exhale out of your nose and mouth while your face is in the water. As you turn your face to the side (so your mouth is out of the water), inhale quickly. Never hold your breath!

Tip 3: Position

Focus on a long, flat head-spine-line, keeping your hips high. If your feet sink, look down at the bottom of the pool. No more than a sliver of the back of your head should be visible above the surface. When inhaling, don’t lift or over-rotate your head to look at the sky. In between breaths, keep it still, in one position.

Tip 4: Bilateral breathing

Bilateral breathing (breathing on both sides) is best, but some great swimmers only breathe to one side. The key is to find a pattern that you can comfortably sustain for 3.8km and that doesn’t leave you gasping.

Tip 5: Session choice

Try to do three swims a week. One can be an easy swim; 1,500m or so at a very relaxed pace. Then do a race-pace session. To find out this pace, time how long it takes you to swim 100m at a comfortably hard effort. Try doing 5 x 100m at this pace with 10-15secs rest in between. It would be good if, before race day, you can do a total of 2km at this pace. This can be broken down into 100m, 200, 300m intervals with about 10secs rest.

Warm up and warm down with 300m or so of very relaxed swimming. For your third session, do short distances but faster with longer rest: for instance, 20 x 25m with 30secs rest after each 25m. After a month, you can progress to 10 x 50m. Do some steady swimming either side of this set.

Tip 6: Practice

Do open-water practice; you can do it in a pool if you don’t have access to the real thing. Try ‘pack simulation’ with a few people around you. Swimming with your eyes closed is good to prepare you for reduced visibility.

Remember that you’ve already come so far. It may not always be easy, but you will achieve your goal. Good luck!

More advice from Chrissie Wellington

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Chrissie Wellington OBE is a retired, British professional triathlete and four-time Ironman world champion. ​ She held all three world and championship records relating to ironman triathlon races: firstly, the overall world record, secondly, the Ironman World Championship course record, and thirdly, the official world record for all Ironman-branded triathlon races over the full Ironman distance. She remains the world record holder for Ironman distance (8:18hrs). Chrissie won the Ironman World Championship in three consecutive years (2007–2009), but could not start the 2010 World Championship race because of illness. She regained the title in 2011. She is the first British athlete to hold the Ironman world title, and was undefeated in all 13 of her races over the Iron distance. She is the only triathlete, male or female, to have won the World Championship less than a year after turning professional, an achievement described by the British Triathlon Federation as "a remarkable feat, deemed to be a near impossible task for any athlete racing as a rookie at their first Ironman World Championships." Since retiring in 2012 Chrissie has completed countless endurance events, from cycling sportives, to marathons and ultra-marathons and even a cross country ski marathon or two! Chrissie was awarded a first-class degree by the University of Birmingham (BsC Geography) in 1998 and a Distinction from the University of Manchester (MA Econ Development Studies) in 2000. ​ Prior to becoming a professional athlete in 2007, she worked for the British Government's Department for Environment, Food and Rural Affairs (DEFRA) as a policy adviser on international development and also managed water and sanitation projects in Nepal. Chrissie now devotes her life to work to improve individual and population health and wellbeing, and specifically interventions to increase participation in physical activity. She is the Global Lead for Health and Wellbeing for parkrun and is committed to engaging people of all backgrounds, ages and abilities in parkrun events, thereby addressing the entrenched health and wellbeing inequalities that impact many countries across the world. Chrissie published her Sunday Times Best Selling autobiography, 'A Life Without Limits', in 2012, and her second book, 'To the Finish Line: A World Champion Triathlete's Guide to Your Perfect Race', in 2017. In 2021, she co-authored and published two fully-illustrated children's wellbeing storybooks with friend and former athlete Susie Bush-Ramsey entitled 'You're so strong' and 'You're so amazing', as a means of sharing messages about belief, trust, love, friendship, trying your best and embracing change. ​ A trailblazer at heart, Chrissie is often advocating for change. In 2014 she joined three professional cyclists in campaigning for and successfully creating a women’s race at the Tour De France. Chrissie was appointed Member of the Order of the British Empire (MBE) in the 2010 Birthday Honours and Officer of the Order of the British Empire (OBE) in the 2016 New Year Honours for services to sport and charity. She was also named the 2009 Sunday Times Sportswoman of the Year and has Honorary Doctorates from the University of Birmingham and the University of Bristol. Chrissie lives with her husband, former professional athlete Tom Lowe, and their daughter Esme in a small village in Somerset.