Group People In Wetsuit Swimming At Triathlon

Could Swimrun be Your Next Sport?

BY Carrie McCusker

Invented in Sweden, the growing sport of swimrun could be ideal for triathletes, runners and swimmers looking for a unique challenge.

It’s a perfect summer morning in Maine, and I’m standing on the edge of the Peaks Island ferry dock looking up the road ahead. Like every race, there is a buzz of energy from the crowd of athletes. Unlike most races, everyone is decked out in fluorescent orange, right down to the safety whistle—and wearing an assortment of swim paddles, pull buoys, and running shoes.

My teammate and I are tethered together with a bungee cord at the waist—a standard practice to help with teamwork throughout the day. He is carrying fins and a kickboard; I am wearing floating shin guards and carrying swim paddles. It’s our third year, and we’re still tweaking our equipment.

In the next six-plus hours we will cover nearly 19 miles of running and five miles of swimming, spread out over nine islands in Casco Bay. Every year the race is different, and with the unpredictability of nature there is no telling what the day may bring. This is Swimrun.

If you haven’t caught the buzz on swimrun yet, 2020 is turning up the volume. It all started in Sweden with an attempt among friends to swim and run through the Stockholm archipelago. Not many people finished, but it became an official race in 2006 and was aptly named “Otillo,” meaning “island to island” in Swedish.

All swimrun events include at least two transitions between swimming and running, with participants often making their way across islands (or chains of islands) via trails, beaches, and roads. The events have gained popularity for the challenge, but also for offering views and accessibility most people never experience.

Despite being a few years behind, organizers in the USA are rapidly expanding, with new events every year. Odyssey SwimRun, which brought the very first Otillo-affiliated event to Maine in 2016, now offers four different races, the newest in Les Chenaux Islands, Cedarville, Michigan. The Otillo World Series, now in its 15th season in Europe, will come to the US for the first time in 2020 with a race on the beautiful island of Santa Catalina, California.

Swimrun can be intimidating. While triathlon controls for transitions, road conditions, and course quality, swimrun is more about dealing with whatever nature throws at you on the day. Racers navigate water crossings with rapidly changing currents; seaweed proliferates in areas, and swells can be unpredictable. Despite these factors, the sport is growing. Co-founder of Odyssey SwimRun, Lars Finager reports:

  •  48% of athletes in the 2019 season defined themselves as being committed to swimrun.
  • 42% added in swimrun races as they fit into their schedule. 
  • 29% of the swimrun athlete population came from a 70.3 or Ironman background.
  • 18% came from shorter course triathlon. 
  • There is an even distribution of participants from road and trail running.
  • Nearly half of the participants are in the 40-49 age group.
  • 54% were male and 46% female.
  • Over one thousand athletes are predicted to compete in the race series in 2020.

This data suggests that a diverse population of athletes is turning to the sport of swimrun for adventure, challenge, and a change of pace.

However, I am questioning all these reasons around mile 18, when I am running over soft sand on a beach and, in my fatigued state, nearly plant my face on the ground. Admittedly, this is a low point. I curse the long beach section (which was added to the course late). Our legs are nearing destruction and the energy-sucking surface just highlights the deficit.

The race emerges onto the road and the air is dead still, the sun is baking; I feel like a potato wrapped in foil. I unzip my steaming suit and remove my swim cap for the first time that day; this is the longest contiguous run segment. My rock-solid teammate makes me laugh at our suffering and we dig in.

At an aid station before the last crossing, I drink as much as I can and feel some gentle revitalization over the next few minutes. Things are OK again by the time we hit the last swim. I get cooled off, and can hang on the tether for the final miles of pavement to the finish line.

I asked Lars what athletes contemplating their first swimrun should consider. Number one, he said, attitude is everything. Part of what makes the experience of swimrun so unique is that it is a true endurance adventure. Not every factor can be controlled, and in many cases you will encounter challenges (like wide temperature swings, slipping on seaweed-covered rocks, or dealing with ocean swell) that you may not have confronted in a race setting. Stay positive, and you’ll find that swimrun can make for a very rewarding experience; not to mention great conversation over your post-race beverage of choice.

Second, Lars says that triathlon training will carry you over 95% of the way in terms of preparation. In other words, a high percent of triathletes looking for a switch in routine (or a fun race to add to their calendar) will be mostly ready to roll.

To supplement your triathlon fitness, Lars suggests some specific preparation learning to swim with shoes and a pull buoy. I’d also add some overall strength and agility. The ability to run off-road and handle technical terrain will help you tremendously with your overall experience and performance. 

For context, here’s a snapshot of the file from a long course SwimRun, gathered from a Garmin Forerunner 935XT. This athlete set the workout to ‘run’ for the entire event in order to get a contiguous map and reading. As you can see, it is evident where the running took place. The road sections tend to have a higher HR than the trails, which required more focus on form and control.

The average HR of 128 indicates an easy endurance run pace for this athlete. That said, the max of 174, which is above threshold for this athlete, and the element of a lower swim threshold HR, means the captured TSS of 329 is well below the actual. Because HR varies throughout the day, ranging from zones 1-4, preparation should involve a variety of training.

As it grows, swimrun offers a lot of potential for triathletes, runners, and swimmers looking to supplement or tweak their standard race calendar. The challenges are broad but invigorating, and participants will travel trails and waters that not many people get to experience in such an intimate way. If you haven’t checked out swimrun already, 2020 might be your year!

Full Distance Triathlon Training Guide Thumbnail

The Ultimate Full-Distance Training Guide

Training Guide

This guide is designed to be used as you train for a full-distance triathlon, with in-depth information on every part of the process. Each chapter is packed with tips, workouts, and insights from triathlon coaches, to give you all the tools you need to succeed.

About Carrie McCusker

Carrie McCusker is a level 2 TrainingPeaks coach and a lifelong athlete who enjoys bringing individual attention to every level of athlete. You can find her on Strava and Instagram or check out her coach profile at TrainingPeaks.

Visit Carrie McCusker's Coach Profile

Related Articles