Sarah Fuller, of Winthrop, succeeded at completing her first Ironman competition at Lake Placid, New York. An Ironman must swim over two miles, run a marathon and bicycle over 100 miles.

There were only hours to go until the annual half Ironman triathlon at Old Orchard Beach, the first for both Laura Gosselin and Sarah Fuller. But before they had even started the toughest athletic challenge of their lives, they got the idea to take it a step further.

“The night before we actually did it, (Sarah) and I decided we wanted to do a full one,” Gosselin said. “Before we’d even done the half. No idea why.”

It was more than brash bravado or a spur-of-the-moment surge in confidence. Two years later, Gosselin and Fuller made good on their pre-race promise, completing the famed Ironman Lake Placid in New York on July 22.

“It was just this crazy idea two years ago, and here we were,” said South China’s Gosselin, 48, who completed the daunting 140.6-mile triathlon in 15 hours, 45 minutes and 8 seconds. “I could not believe that my body had just done that for me, that I asked it to do this thing and it did it.”

Winthrop’s Fuller, hampered by a faulty bike, nevertheless crossed the finish line in 16 hours, 3 minutes and 51 seconds. Participants must finish the race in under 17 hours for the Ironman title.

“Because my finish time could have been better had all things gone according to plan it’s a little disappointing, but I’m still pretty happy that I finished,” she said. “It’s still sinking in that 140.6 miles is a long way to push your body.”

The two began occasionally training together after meeting at Kennebec Valley Coaching, by Fuller’s estimation, three or four years ago, but they travelled different roads to get there. Fuller was driven just by a general fitness interest, running her first 5K five years ago and competing in her first triathlon in Skowhegan the next year.

“For a number of years I’d run and gone to the gym just to maintain some fitness, I didn’t do any competition,” said Fuller, who competed in two triathlons in 2015 and the half Ironman events in 2016 and ’17. “I rode my bike recreationally, and (triathlons) sounded intriguing to do something besides just run to mix it up a little bit. … I was pretty much hooked after that.”

Gosselin, however, took a more complicated route. After struggling with her weight for years, she began running after making a commitment on New Year’s Day in 2006 to get in shape. That became half marathons by 2007 and then triathlons by 2010, and when her sister died in October 2010, five months before she was set to try her first marathon, running became an emotional obligation as well as a physical one.

“I had to go outside, because I wasn’t going to be able to finish it if I didn’t train,” she said. “Had I not had that to do, I would have struggled a lot more that winter. … I was thankful I had that running, because that would have been a very different winter. I just would have been in a totally different place.”

Their motivations were different, but Gosselin and Fuller began to share the same drive as they climbed the endurance sports ladder. Ironman was the next step, and with help from KVC’s Amy Lawson, the two started following a plan to prepare athletes for the daunting event, which is made up of a 2.4-mile swim, 112-mile bike ride and a 26.2-mile run. The plan involved training from the first day of January to the race in July, gradually ramping up the workload until athletes are spending 16-18 hours a week training.

Scheduling often prevented Gosselin and Fuller from training together more than once or twice a week, but they spoke and texted often throughout the months, and Fuller said having someone else go through it as well allowed both to stay committed.

“You really don’t want to go to the pool when it’s 20 degrees out in the middle of February,” she said. “But you’re like ‘Oh no, I agreed to meet you there for a swim,’ so you’re going to show up and do it.”

That dedication paid off when they got to Lake Placid. Nothing about the Ironman is easy. The swim leading off the event is often the most dreaded stage, and for good reason — with everyone still in the race and in a confined area, swimming more closely resembles a waterlogged melee than laps at the YMCA.

“You’ve got 2,500 people all in the water at the same time,” Gosselin said. “There’s a lot of kicking and splashing, and I got kicked in the jaw and I got a bruise on the top of my hand.”

“They kind of describe it as a scrum,” Fuller said. “(You) get a little bit beat up in the water.”

The race starts at 7 a.m. and competitors have to finish the swim by 9:20. Gosselin and Fuller did, and then went to the bike stage, where Fuller ran into problems both mechanical (her chain acted up, allowing her to use only her lower speed gears) and physical, as knee and foot injuries began to flare up.

“I ended up falling three times,” she said. “But I was happy to make the (5:30 p.m.) cut-off.”

Biking was Gosselin’s weakest area coming in, but aside from two stops along the way, she rolled through the event without incident — even braving cold and rainy conditions that forced a number of athletes to tap out.

“I tried my best to train at home in every kind of possible weather,” Gosselin said. “I really hate the cold but I tried to train in everything possible in case it happened on race day, which it did.”

All that was left was the running portion, just a mere marathon at the end of a long day. By that point, however, Gosselin and Fuller knew they were past the worst of it.

“I was so happy that I was out there,” Gosselin said. “I knew I was going to finish at that point. As tired as I was, I didn’t care. I was just so happy.”

“Even with the issues I was having, I never felt once that I wasn’t going to make it through,” Fuller said. “The energy of the day and the excitement of being there and having this opportunity to compete at Ironman is really magical, and it carried me through a lot.”

A party was waiting when they crossed the finish line, but both said conquering one of the hardest competitions on the continent was all the celebration they needed.

“I think it’s kind of empowering for people to see you don’t need to be really fit to do these things,” Gosselin said. “You need to be determined and not quit.”

Forget quitting. Both Gosselin and Fuller said they’ll be back in 2020.

“It just makes me feel proud,” Gosselin said. “It’s a feeling of pride that you put all that work in, and this is what you get for all that work.”