Turn on the television this July and you might catch Tour de France footage of razor thin athletes racing bicycles up mountain passes. Many of them — the best — look as though they might blow away in a stiff breeze. Even among cyclists, the bodies of top Tour de France racers are in a class of their own: stick figure arms, chiseled quads, and lungs that could fill a hot air balloon.
As Corey Hart, Ph.D., a coach at Max Testa Training, puts it, they bear a passing resemblance to a T-Rex, with its mismatched limbs; essentially a pair of thighs attached to an unusually well-tuned aerobic jet engine. “They’re mainly quads," says Hart. “We know from studies that they have significantly more quad mass than runners or just your everyday person.”
Quads that could crush Everest (if it was paved) aren't the only thing that sets Tour de France racers apart. Here are four more ways — from both genetics and thousands of hours of training — that these cyclists are unlike anyone else on Earth.
The top Tour riders are exceedingly lean. "A lot of climbing is physiology," says Eric Sternlicht, Ph.D., a kinesiology professor at Chapman University. "They have to have the right anatomical structure and very low body weight. If they’re tall, they better be like a Chris Froome." Defending champion Froome is 6’1” and reportedly weighs 147 pounds. The Tour de France is almost always won or lost on mountain climbs, and a racer's performance and uphill speed boils down to their power output divided by bodyweight.
Just how skinny are the racers? “On average, it’s around 8 percent body fat,” Hart says. Though it’s difficult to measure body fat percentages across the population, an average person might come in around 25 percent. Podium contenders don't like to share weight or fat numbers, but when support rider Jens Voigt was preparing for his penultimate 16th Tour in 2013, he claimed his body fat had dropped to 3.7 percent.
Tour riders are comparable in body fat percentage to an NFL wide receiver, says Hart. But take Steve Smith, a wide receiver for the Baltimore Ravens. He stands 5’9” and weighs 185 pounds. Two-time Tour de France winner Alberto Contador is also 5’9”, but weighs 137 pounds. What sets the two apart is the muscle fiber types they develop.
“You’ll see the fast-twitch muscles on a wide receiver, it’s like a body builder,” Hart says. “They’re shorter muscle fibers that are bulkier. The Tour riders’ slow-twitch muscles will be longer and stretched out.”
In terms of raw performance, the aerobic capacity of Tour riders really distinguishes them from other athletes. Tour racers typically have bigger hearts and have larger blood volumes, says Sternlicht. "You might call them genetic anomalies." The best measure of that aerobic capacity is the VO2 max, their maximum oxygen consumption measured per body weight per minute. “If you look at NBA basketball players, their VO2 maxes are around 55,” Hart says, “and the average person is around 35.” Tour riders on average have a VO2 max of 75, and Tour winners will often be higher. Three-time Tour champ Greg Lemond reportedly had a VO2 max of 92.
Within the Tour de France, there's still a variety of shapes and sizes. Chris Froome, with his lanky, stretched-out arms and legs looks different from a sprinter like Mark Cavendish, who is shorter, more muscular (but still incredibly lean), and almost bullet-shaped on the bike. Typically, though, elite cyclists will have longer femurs than most athletes, which gives them extra leverage when they push the pedals.
“In the past, you’d hear people talk about Greg LeMond and how long his femurs were,” Hart says. “If you look at basketball players, that section below the knee [the tibia] is typically longer than the femur.”