After winning two Olympic medals in two different sports at consecutive Games, Rebecca Romero has decided to embark on a third - and possibly her hardest - sporting challenge.
The 32-year-old Briton, who won a rowing silver at the Athens Games in 2004 and then a track cycling gold in Beijing in 2008, decided to become an Ironman competitor and finished sixth in her debut race in July to qualify for October's World Championships in Hawaii.
Romero left Britain's track team in 2011, unhappy at changes made to Olympic cycling in 2009 that saw her event removed from London 2012.
She says Ironman has helped her come to terms with
"My aim had been to go to London and win a gold medal," she told BBC Sport.
"It was really disappointing that I spent a few years training and things didn't work out. I'm at ease with that having happened and not making it to London, but I just got to the point where I felt like I needed a closure point."
Ironman is a 2.4-mile swim, a 112-mile bike ride, followed by a 26.2-mile run.
Romero says she decided to enter the Ironman UK in Bolton after "a momentary loss of common sense" and gave herself just seven months to train.
"That's how far I was behind where I needed to be," Romero adds.
"I thrive on being rubbish and being desperate to get better and working out the processes of how to do that, to do it sensibly and make small steps for that bigger long-term aim."
Surprisingly, Romero says the 112-mile bike ride was the worst part for her. "Everyone thinks that because you're Olympic champion on the bike, you should absolutely storm that," she says.
"But all I trained to do is be fast for three kilometres [1.8 miles] on a bike. Endurance-wise, to extend it for that long, that's where I struggled."
Romero finished sixth overall in Bolton and second in her age group to secure her place at the iconic World Championships in Kona, Hawaii on 13 October.
"I've shocked myself," she adds. "I didn't expect that I would be able to get to the start line of an Ironman, let alone finish my first one in a reasonable time and qualify in my age group as well."
She says she had mixed feelings at the finish line when she was told she had qualified for Kona.
Instead of "jumping for joy", the thought of another Ironman filled her with dread, which she admitted was a "horrendous" prospect.
But she adds: "To mix it up with the big guns, the real Ironman athletes, I couldn't turn it down."
Romero says her involvement with Ironmans is likely to be fleeting, revealing that her athletic achievements have started to take their toll on her body.
"I thought that the Ironman in Bolton would be my last," she says. "I really thought, crossing that finishing line, that that would be it, no more training, no more serious challenges, just a normal life.
"But never say never. If I can get a new body, get fixed and not feel the pain, then I'd love to keep going.
"I really don't know what the future's going to hold, but my priorities are definitely going to change."