Swimrunning is ‘all fun with a bit of crazy mixed in’

The original swimrun competitors carried backpacks of dry socks and food and other supplies. Today companies are making special gear for the runners/swimmers.
The original swimrun competitors carried backpacks of dry socks and food and other supplies. Today companies are making special gear for the runners/swimmers.

CASCO BAY, Maine — Once the thick veil of fog lifted, a horn sounded and hundreds of athletes wearing running shoes and wetsuits leapt into Casco Bay and began swimming — hard. Their goal: To swim from one island to the next, scrambling out to run across each island where they would dash along singletrack trails, follow paved roads by summer cottages, bushwack through thick brush, or slog their way through sand or across scree-covered terrain.

They moved in pairs, often tethered together with a thin bungee cord. All told, they would swim 4 miles and run 10 miles as they connected nine islands in Casco Bay. Welcome to the new sport of swimrun.

“That’s what we used to do when we were kids,” says John Stevens, one of the competitors,who summered on Casco Bay’s Little Diamond Island as a kid, and now lives in Portland with his family. “I grew up running around all the islands, and rowing and swimming between them. . . . I’m familiar with the distances and the tides, but I had no idea what to expect during this race, which is what I loved about it.”


Last summer, 240 athletes participated in the Casco Bay Islands Swimrun, the first event of its kind in the United States. Competitors swam anywhere from 270 to 1,700 yards between islands, and ran between half a mile to just over 4 miles across islands.

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“The race was all fun with a bit of crazy mixed in there,” says Erin Hunter of San Diego, who won the women’s division with her partner, Emily Finanger from The Woodlands, Texas. “There was a lot of climbing over slippery rocks, dealing with ocean currents, and swimming through beds of sea grass. On one island, we got tangled in seaweed and looked like sea monsters climbing up onto shore, but we were laughing the whole time.”

Lars Finanger, founder of Swimrun USA and co-race director for the Casco Bay swimrun, contends that “the most important element is having a fun, adventurous attitude and rolling with the punches. Shit happens,” he says. “You’re going to get a bloody elbow and knee, and you’re going to have to keep rolling.”

The sport attracts competitive swimmers, runners, adventure racers, triathletes, and people drawn to its unpredictability. Sign up for a running race or a triathlon and you cover exact distances and precisely defined routes. With swimrun, athletes swim their best lines from island to island — there are no buoys marking the way — and take currents and conditions into effect so they don’t drift off course and add mileage.

“There’s a flag where you get in and a flag where you get out on each island, but the challenge is that there’s no exact way to get from Point A to Point B.” says Bridget McCoy, one of last year’s competitors from St. Paul, Minn. “If you’re on the ocean and it’s really foggy, it’s your job to take out your compass and figure out where you need to go.”


On land, racers follow a running course that’s marked with flagging tape where possible, or they use their best judgment and a map and compass to make their way over the terrain.

“There’s no person waving a flag, blowing a whistle, and saying ‘Turn right here,’” says Sara McLarty, a former pro triathlete who competed in last year’s Casco Bay race with friend and Xterra world champion racer Misty Becerra. “At one point, Misty and I had to stop and backtrack on Peaks Island to make sure we were on the right trail.”

Adds Finanger, “You’re starting at Point A and going to Point Z, and taking what nature gives you in between.”

In fact, an appreciation for nature and the beauty of the landscape lies at the philosophical heart of this sport. The idea for swimrun traces back to a drunken night among friends at a seaside resort in Utö Värdshus, Sweden. As the story goes, four guys walked into a bar and, many drinks later, came up with the brilliant idea of racing each other from one end of the Stockholm archipelago to the other — a distance of 75 kilometers (about 46 miles) — with the losing team having to cover dinner, drinks, and the hotel for the losers.

“We were talking about how we’ve traveled around these islands by boat and kayak, but how we’ve never gotten to really see a lot of the islands,” says Mats Andersson, one of the sport’s founders. “The idea was we had to go up on the islands so we could see them along the way.”


Only two teams showed upon race day, wearing surf wetsuits and old sneakers, and carrying backpacks with sleeping bags and other supplies. It took them 23 hours to complete the distance, including a stop to sleep under a tree.

“It was a perfect day and we thought, ‘Everyone needs to do this,’” says Andersson. “It was such a simple way to see so many places, and ones you normally pass by. There were places where you thought, ‘I just want to sit down and enjoy this beautiful place.’”

Andersson and his cohorts soon met Michael Lemmel and Mats Skott, adventure racers and organizers who agreed to help put together an official swimrun race. They mapped out the course and staged the first race in 2006. This time, 10 teams showed up, but only two finished. Some still towed dry bags with socks, shoes, and a towel.

“People would sit down, dry off their feet, put their socks and shoes on, and then start running,” says Mats Skott. “There are 26 islands, so 50 transitions, and they were sitting down for hours. It was more of an expedition at the beginning, but now it’s slimmed down to a quick in and out of the water.”

The idea took off, though, and by 2012, Lemmel and Skott organized three swimrun races in Sweden, and had to turn away 400 teams (max participation in each race is 120 teams for safety reasons and to minimize environmental impact). That year, one of the racers coined the name Ötillö, meaning “island to island” in Swedish. Now, in 2017, more than 400 swimrun races exist worldwide, including Switzerland, Spain, South Africa, New Zealand, Croatia, and Thailand. The original Ötillö event serves as the world series for swimrun, with participants from 35 countries.

“You really get to experience a Sweden that no tourist gets to see,” says McLarty, who has done the Swedish race twice. “We were running on uninhabited islands, or islands that had homes but no roads, just unpaved trails. Maybe two or three of the islands had paved roads.”

In August 2016, native Mainer Jeff Cole and Finanger, a pro triathlete and adventure racer, launched the Casco Bay Islands Swimrun. “We knew we were on to something,” says Finanger. “We opened the lottery and had more than 600 applications for 100 spots.” This year, more than a dozen swimrun races will take place across the country, in California, North Carolina, Georgia, New Jersey, and Washington.

“For us, it is fantastic to hear about the excitement of the sport,” says Lemmel, from Stockholm, who earned his undergraduate degree from Brown University, and lived in North Conway for three years. “We wanted to create an adventure and nature experience, and challenge our racers to step out of the box a little bit. You can’t control anything in swimrun because the environment changes all the time.”

One of the biggest challenges for many, however, is having a partner. Racers compete in the men’s, women’s, or mixed division. Each team has two people, and those two racers must stay within 10 meters (30 feet) of each other throughout the swim and 100 meters during each run.

“Being a swimmer and a triathlete, I’ve only ever done individual sports,” says McCoy. “Doing something where I’m completely dependent on another person is totally foreign to me.”

Adds McLarty, “That’s the biggest new aspect of multisport that swimrun is bringing to the endurance community. It’s not you in your own head, it’s you and your teammate relying on each other, and being able to communicate and work together. It’s important to pick a good teammate, someone who’s compatible.”

Another aspect that’s evolved in recent years is the gear, or lack thereof. The challenge is to minimize what you take, and make everything count. During the early races in Sweden, racers towed dry bags stuffed with backpacks, extra clothes, sleeping bags, and food. One team brought a vacuum-packed steak dinner.

“It was like the Victorian days — bring everything with you and we’ll set up camp,” says David Thompson of St. Paul, Minn.

Today, racers bring only what’s necessary, and can choose from specialized gear created for swimrun athletes. Gone are the days of surf wetsuits and old sneakers with holes drilled in the soles for drainage. Companies such as Orca now make swimrun-specific wetsuits that have flexible neoprene material, pockets for stashing energy food, a built-in whistle, and front zippers and removable sleeves for cooling off on runs.

Icebug, a Swedish company known for its high-traction winter and orienteering shoes, makes a trail-meets-track shoe with super grippy soles that help racers scramble up slippery rocks and navigate wilderness terrain. These lightweight shoes drain quickly and have lightweight EVA foam that helps them float while racers swim.

Many athletes use swim paddles for extra propulsion and swim buoys to help keep their legs afloat, and some even bring fins. All racers must have a waterproof pressure bandage, an inflatable safety float with a GPS, a compass, and a map.

“The equipment is designed to make it safer for you, and to also offset those shoes you’re dragging behind you,” says Finanger. “The lighter, the better.”

Racers must also finish the race with every piece of equipment and energy wrapper they start with: If you bring swimming fins and decide you don’t need them, you still have to carry them to the finish — no stashing them under a bush to retrieve later.

Many athletes also attach a tether — typically a thin bungee — between them, especially during the swim.

“It was tricky using it, but it gave me peace of mind that we weren’t going to wander too far apart,” says Stevens.

Few rules govern the sport, but the ones that do encourage a true sense of sportsmanship and a respect for nature. “The spirit of swimrun is Good Samaritan style,” says Finanger. “If you see a fellow racer in difficulty, your race doesn’t matter, you need to stop and tend to that person.”

Adds Thompson, “If you want to enjoy swimrun while it’s still a grassroots race, then this is the time to get out and do it.”

If you go . . .

Swimrun events

Casco Bay Islands Swimrun

Aug. 13

North Carolina Swimrun

Oct. 29

California Swimrun

May 7


April 23

New Jersey Swimrun

Aug. 19

Kari Bodnarchuk can be reached at