For reasons that will become obvious, Megan Guarnier’s family likes to tell the story of the time Megan refused to ride her bike. This was years ago: she was just a little kid, out on a ride with her mother and other relatives. It had already been a long day, and her brother, Bryan, kept nudging his front tire into Megan’s rear wheel.  Little Megan abruptly stopped. She’d had enough of her bike and this stupid bike ride.  “She got off her bike and said, ‘I’m not going any further,” recalls her mother, Mary Burns.  “I am pretty stubborn,” Guarnier says, laughing. “I wasn’t going to go another pedal stroke.”  Guarnier held firm to her protest, sitting on the side of the road with her grandfather and her bike as an uncle rode all the way home, fetched his car, returned to scoop her up.  Guarnier’s family thinks that story is hilarious now, because that stubborn girl on that roadside? She’s become one of best bike riders on the planet. Guarnier, a native of Glens Falls, N.Y., is currently the No. 1 ranked women’s road cyclist in the world, the recent winner of the prestigious Giro Rosa stage race, and a serious contender to win gold Sunday in the women’s road race at the Summer Games in Rio de Janiero.  Today, you can’t get Megan Guarnier off the bike if you tried.  “When it’s 42 degrees outside and rainy and windy, she will still go out,” says Guarnier’s husband, Billy Crane. “It’s more of a challenge to talk her out of a ride than it is to go do it.”  At 31, Guarnier is a quiet star in a sport deserving of more attention, an all-around talent who becomes a factor in virtually every race she enters. Her 2016 season is already spectacular: In addition to the Giro Rosa, she won the women’s Tour of California, the Philadelphia Cycling Classic, the Durango-Durango Emakaumeen Saria, and the U.S. National road race championships.  Still, Guarnier is candid about what would make this season perfect.  “A gold medal,” she says.  Like a lot of women in pro cycling, Guarnier grew up specializing in a different sport. As a kid, she dreamed of making the Olympics as a swimmer, idolizing Jenny Thompson. But chronic shoulder injuries wore her down. Not long after Guarnier, a high-school valedictorian, enrolled at Vermont’s Middlebury College, friends talked her into entering a collegiate bike race.  She won it—and was hooked.  “I threw myself at it as much as I could,” she says.  Such single-mindedness is a Guarnier characteristic. Her college friend Danielle de Garcia says she had to yank Guarnier, a neuroscience major, away from the library “and force her to have fun.” Mary Burns recalls her daughter at age 2, spending extra time to make sure her socks were just right (bike people tend to be sock freaks, so this may have been an indicator Guarnier would become an elite cyclist.)  “Once she became focused on something, she was very focused,” says Burns.  “We like to say she doesn’t have ‘hobbies,’” says de Garcia. “When Megan goes in, she goes all in.”  After graduating from Middlebury, Guarnier decided to give pro racing a shot, even if she had little idea how to get started. She joined a team and moved to California (she and Crane are now based in the San Mateo area, and also purchased a fixer-upper in southern France.) Women’s pro racing isn’t a terribly lucrative career choice, and so for years, Guarnier kept a part-time job—doing “Probabilistic Risk Assessment” for nuclear power plants.  “You analyze the risk of various parts and people failing to do their job—ultimately avoiding a meltdown,” Guarnier explains.  You looked for Homer Simpsons?  “That’s what people always say!”  Back on the road, Guarnier would transform from a promising rider into a savvy racer. Such evolutions take time—even the best racers describe the trial and error it takes to learn techniques and strategy, the necessary teamwork, the mental aspect, the mistakes of expending energy too early or too late. Nearly everyone is humbled at some point. Guarnier spent a 2008 stretch in Europe getting dropped from every race she entered.  “That can be motivating or completely discouraging,” Guarnier says. “I said to myself, ‘I don’t know what they’re doing at the front [of the race], but that’s where I want to be. I want to be at the front, making the girls in back suffer.”  In 2012, Guarnier set aside her part-time job to focus on racing and training full-time. Good results followed, but she was passed over for the Olympic team at the 2012 Games in London—a major disappointment. Guarnier admits she wasn’t sure if she could stay hungry until Rio. Do I actually want to do this for another four years? She asked herself.  She would channel her disappointment into motivation. Guarnier’s coach, Corey Hart, says Guarnier worked to improve every aspect of her riding, in particular climbing. They looked at what Hart calls “economy”—Guarnier’s “ability to take in oxygen and most efficiently transfer it to power”—and made refinements to her positioning on the bike and her form when riding out of the saddle.  “She’s continually adapting,” says Hart. “Anything can be thrown at her, and she’ll handle it.”  In 2014, Guarnier joined Boels-Dolmans, a Dutch-based cycling team which resembles the Golden State Warriors of women’s bike racing. Boels is stacked: Guarnier’s teammates now include reigning World Champion Lizzie Armitstead, two-time U.S. Olympian and hour-record-holder Evelyn Stevens, and time trial and track champ Ellen van Dijk of the Netherlands. All will be in Sunday’s race in Rio, including Armitstead, who was given last-minute clearance after three missed drug tests resulted a provisional suspension last month.  On a team of stars, Guarnier has emerged as a powerhouse. “You can’t win a Giro by just climbing strong or sprinting strong,” says Guarnier’s Boels-Dolmans teammate (and frequent road roommate) Christine Majerus. “Everything needs to come together. Physically, mentally, team support, and, of course, a little bit of luck. Megan has it all…and it came together perfectly this year.”  Derek Bouchard-Hall, the president and CEO of USA Cycling, praises Guarnier’s “remarkable” combination of power and endurance: “If you can’t get away from her and you can’t beat her for the sprint to the line, you can’t beat her. And right now, it appears virtually no one in the world can.”  Guarnier has made no secret of her Rio ambitions. Her third-place finish at last September’s World Championships in Richmond, Virginia locked up her slot for the 2016 U.S. roster—a huge relief entering the season. Early in the year, she traveled with Hart to Brazil to train on the hilly course, and calls it “the most challenging I’ve ever seen,” with flat and windy portions, a cobbled stretch, a tough climb and a tricky, technical descent. Hart believes the course is well-suited for a rider like Guarnier, naming Armistead, Anna van der Breggen of the Netherlands and the young Polish rider Katarzyna Niewiadoma as rivals to watch.  Women’s cycling is still a sport that struggles for the media coverage and the public eye, so the Olympics is a hugely significant race. For Guarnier, a victory in Rio would be the ultimate payback for a long and often solitary road of training and commitment. “I might put it down as ‘Life Goal Validation,’” says Billy Crane, Guarnier’s husband, laughing.  Guarnier can’t wait. Sunday will be fun.  “That was something I promised my mom,” she says. “She made me promise I would retire when it stopped being fun.”  Family who remember that abandoned ride years ago probably can’t help but laugh. Megan Guarnier is still on the bike, having the time of her life.  Write to Jason Gay at Jason.Gay@wsj.com
Rio Olympics 2016: Megan Guarnier, who used to do risk assessment for nuclear power plants, has risen to a No. 1 ranking in women’s road racing and now eyes gold