She’s the best runner in Ironman history, but Mirinda Carfrae is risking it all on a new cycling-focused training strategy.
This article was originally published in the Sep/Oct 2012 issue of Inside Triathlon magazine.
Mirinda Carfrae ran out of T2 during the 2011 Ironman World Championship and started ticking off 6:30 miles. The marathon cruelly began in the heat of the day, and the sun roasted her from above while black pavement reflected the rays from below. Humidity gummed up the air. Carfrae’s compact body was built for these conditions, allowing her to pick up the pace to 6:20 miles undeterred. Her shoulders methodically rolled forward then back, using her hip, core and upper body muscles to drive into the ground with each step. Like a track athlete, her heels skimmed her butt as she flicked through every stride. Carfrae was created to run the Kona course and had trained herself exquisitely, but she wasn’t gaining time on Chrissie Wellington.
Carfrae won the 2010 Ironman World Championship while Wellington, undefeated over the distance, sat out due to illness. The fleet-footed Aussie earned the title, but some looked at her victory with an asterisk, having missed the opportunity to beat the best.
Wellington was again dealing with hurdles on race day in 2011. Two weeks before Ironman Hawaii, she crashed on a training ride, leaving her with injuries that made her more vulnerable than ever. Despite running with a pronounced hitch in every stride and a perplexing, cock-eyed look on her face that depicted her agony, Wellington took time from Carfrae on the bike, then raced her to a draw on the run. Wellington won her fourth world title on a severely damaged chassis, and Carfrae crossed the line three minutes later.
Carfrae went to raise her arms at the finish, but dropped her fists before they got above her shoulders. With grace and professionalism, Carfrae warmly congratulated Wellington then embraced her boyfriend, family and coach at the finish line. Carfrae had added another extremely impressive performance to her already sterling record in Kona. A win and two second-place finishes is a phenomenal track record by any standard, but world titles are hard to come by in the era of Chrissie Wellington, and Carfrae’s body language and that of her closest supporters revealed her disappointment with second place.
As she came to grips with her runner-up finish, Craig Alexander was exalting in his third Ironman world title.
In 2010, Alexander tried in vain to bridge up to a breakaway group containing eventual champion Chris McCormack. He floundered on the Queen K Highway before ultimately settling in to his own personal time trial in an effort to minimize the damage while the group of four leaders worked together to increase it. His efforts weren’t enough. Alexander forfeited more than seven minutes on the bike, a gap even he couldn’t overcome on the run. He finished fourth.
In 2011, however, Alexander was the one shedding bodies on the way back from the turn-around in Hawi, putting minutes into all but three others before capping his record-breaking victory with another scorching marathon. He regained the laurel wreath by transforming himself on the bike, not by further improving his run.
One year earlier Alexander stood in a position remarkably similar to Carfrae’s. Now she needed to make that same transformation.
Mirinda Carfrae has always been a strength rider. To ride faster, she simply pushes harder against the pedals. In that sense, Carfrae is made from the same mold as Caroline Steffen, Wellington and Lance Armstrong’s former rival Jan Ulrich. But unlike those three, Carfrae is small. At 5-foot-2 and 115 pounds, she simply isn’t strong enough to torque her way to an elite bike split. After years of success using this big-gear, slow-cadence strategy (coupled with her ability to dominate the run), Carfrae decided to make a change this winter to see if she can take her performance up a level.
After Kona 2011, Carfrae amicably split with long-time coach Siri Lindley—herself a two-time ITU world champion—and started looking for a new partner to help her get faster, specifically on the bike. “Things are changing,” she says. “Women now are really taking hold of the bike and really riding fast.” With her marathon split already approaching 2:50, Carfrae has to look elsewhere to dramatically improve. After considering several options, including cooperating with her friend and race-day rival Julie Dibens, Carfrae chose to work with the person who helped reengineer Alexander as a cyclist.
Mat Steinmetz was the fitter who made dramatic changes to Crowie’s position on the bike. He helped Alexander understand the connection between his hydration strategy and core temperature. He conducted the wind tunnel test that spurred a mid-season bike switch. He helped demonstrate that Alexander wouldn’t suffer from using an aero helmet or streamlining his hydration accessories. The pair experimented with these changes before Alexander was beaten at the 2010 Ironman World Championship, but it was that defeat that finally spurred him to abandon the conservative strategy that had carried him to phenomenal success in favor of a more progressive approach. Once his adversaries learned to exploit his weakness, Alexander was willing to take a risk to prevent it from happening again. Carfrae saw at the 2011 Ironman World Championship that she wasn’t yet ready to beat even an injured Chrissie Wellington. After that was when she decided to take a similar gamble.
Steinmetz had been helping Carfrae with her bike fit for two years, and he became her full-time coach when she returned to Boulder, Colo., after Ironman Melbourne this spring. Her equipment selection was already fairly dialed in, but Steinmetz observed several areas where Carfrae could improve, outside of strength and fitness.
Carfrae’s natural inclination is to mash the pedals because that’s how she has always ridden. “Even as a junior growing up, I always went to bigger gears,” she says. This philosophy was further reinforced during her time training under Lindley, who learned the virtues of big-gear riding from her former coach Brett Sutton, widely considered the most successful Ironman coach ever. Sutton is a proponent of riding a low cadence during Ironman events to put stress on the athlete’s muscular system while keeping heart rate and metabolic rate low. “We took those training philosophies and put it into my plan and it worked really well,” Carfrae says. “I’m not sure if it was right or wrong, but it definitely gave me a lot of success.”
Power on the bike is a combination of torque—how hard the athlete pushes the pedals—and angular velocity, the speed at which the pedals turn. Steinmetz is trying to tweak the way she creates power. He is training her to spin faster, not push harder.
Carfrae’s preferred cadence on the flats has been around 70 revolutions per minute. That number drops when she comes to a small hill. Rather than flicking through the gears to save her strength, Carfrae’s habit was to leave the bike in gear and jump out of the saddle to power over the top. The pair found these short grind sessions used to crest hills were burning her strength. “She doesn’t realize when she stands up, she’ll spike her power to 400 watts,” Steinmetz says. “She’ll be cruising along at 200–250 watts, and she comes across a roller and because she’s always been bogged down by cadence her immediate reaction is to stand. She has never had any feedback on what her effort is like, so she ends up cranking the power above 300 watts.” Every spike was not only creating muscular fatigue, but it was counteracting the low heart-rate strategy. Now she’s training with a power meter for the first time since she was a junior to better understand and stabilize her effort. “You want to increase your power over a roller,” says Steinmetz, “but also make sure you’re not redlining so drastically. Using the power meter she’s getting the feedback on what she’s actually doing and how she’s riding—how to use her gears [efficiently]. Sometimes, spinning [high revs] produces as much power as getting in the big gear and torqueing it.”
Carfrae has no intentions of spinning like Lance Armstrong’s frantic cadence, but she is striving to get into the low to mid-80s. Overhauling her pedaling technique despite succeeding with the big gear strategy has her a bit anxious. “It is a drastic change for me because I’ve always ridden a lower cadence and it does feel like a bit of a risk,” Carfrae says. But Carfrae’s self-imposed measure of success and failure, the need to improve every year, and her desire to claw up to Wellington’s level makes it worthwhile.
To help break her ingrained pedal mashing habit, Steinmetz rides alongside Carfrae on a moto-scooter during many of her key cycling workouts. He keeps close tabs on her effort using a Garmin 800 cycling computer mounted to his scooter. Before each session, Steinmetz pairs this computer to her power meter so he can see her cadence and power in real time during the workout. Watching instantaneous data gives Steinmetz the opportunity to offer occasional reminders (“spin a little faster”) and to change an interval on the fly to ensure her cadence doesn’t bog down.