After Chris Froome cut back on carbs for more protein, he lost 20 pounds, started winning the Tour de France, and became a millionaire

Chris Froome on Sunday won his thirdTour de France title in four years, and yet his victories were many years in the making. So much is needed to win the Tour — among other things the right genes, a super-strong team with a big budget, the best bikes and gear, moral support, motivation, the right mind-set, and hard training. But Froome also had to lose significant weight, and he has developed physically from a younger and stockier version of himself into the quintessential stage racer: lean, light, and strong.

When Froome turned pro in 2007 at age 22, he weighed 167 pounds. Now, at 31, he is often cited as weighing 147 (in his 2014 autobiography he said he was 66 kilos, or 145 pounds). The 20-pound weight loss has allowed him to thrive on the bike, especially in the mountains. In scientific terms, his power-to-weight ratio— a key measurement used to express an athlete's performance — is about 6.25 w/kg, the envy of just about every cyclist. After the trimming, Froome is thought to have increased his power to weight by 10%.

"His success can be put down to a massive loss in weight, helping to explain his improvement from also-ran to Tour de France winner," William Fotheringham at The Guardian noted.

"The engine was there all along," Jeroen Swart, a sports physician and exercise physiologist at the University of Cape Town, told Richard Moore for Esquire. "He just lost the fat."

Hello, protein — goodbye, carbs

For the first several years of his professional racing career, Froome had a modest résumé. By far his best result came in his fifth year as a pro, at the end of the 2011 season in the Vuelta a España, or Tour of Spain, where he finished second overall, won a stage, and wore the leader's jersey. Until then, Froome was largely unknown.

In the years leading up to that remarkable performance, Froome had been carrying all kinds of extra weight — tipping the scales at up to 167 pounds. In a 2014 interview with Paul Kimmage for the Irish Independent, Froome said he had "always been aware of the weight issue" but took it for granted: "I don't think I necessarily thought that I could go much lower than [69 kilos/152 pounds] and apparently I have. I've gone a good three kilos lower [66 kilos/145 pounds] which is huge."

Michelle Cound, now Froome's wife, said in the same interview that he "starved himself" before his breakout performance:

MC: He starved himself before the Vuelta, and then he came back to South Africa and that's when we started dating. I've always had a bit of an interest in sports nutrition and my view was that he could still train on more protein and cutting back on the carbs at certain times. And also making sure he wasn't hungry, so having more meals, more often, things like that.

CF: But smaller portions. Basically, I think I lost the weight for that 2011 Vuelta in an unhealthy way; I was starving myself trying to get the weight off and I don't think that's healthy or sustainable. But since I've been with Michelle I've learned to do things in a ...

MC: It also keeps your weight more stable throughout the year, so you're not starving yourself, and then after a Tour you want to eat everything.

CF: (laughs) I still do.

MC: Especially the carbs, he's got such a sweet tooth. But he's found now that if he does cut back on carbs the weight does come down a lot easier than it did in the past. And cutting out foods like breakfast cereals and a lot of the wheat products and bread but still eating enough food — the right food — that he is able to not feel hungry during the day. If you look at his build from the 2011 Vuelta compared to now, he's still lean but his muscles look a lot more defined. So now he has found a way of doing it ...

In July 2012, 11 months after starving himself to ride well in the Vuelta, Froome finished second in the Tour de France. Then he won the race outright in 2013, 2015, and 2016. (He was favored to win the 2014 Tour but crashed out the first week.)

As Froome told Kimmage: "In the Vuelta that year (2011), I think my muscles were probably lighter. I was quite gangly. You wouldn't look at me and say, 'That's someone who's strong.' Whereas now, my diet is a lot more protein based. I've cut back on carbs completely but I'm not losing muscle."

Big lungs too

It's not just about being light. Froome has an exceptional VO2 max— 88.2 — a key performance indicator that measures the maximum amount of oxygen an athlete can use.

"The general population has a VO2 max of 35 to 40, with highly trained individuals in the 50s and 60s," AFP reported. "A few athletes have been measured in the 90s, including three-time Tour winner Greg LeMond. Phillip Bell, a senior sports scientist at GSK, told Esquire: 'Froome's values are close to what we believe are the upper limits for VO2 peak in humans.'"

It all means that Chris Froome has a huge, and hugely efficient, engine. When he won his first Tour he was already down to his ideal race weight of 147 pounds, which he has kept to these past few years, and it has paid off handsomely. He has three wins in the world's biggest bicycle race and earns at least $5 million a year — massive for a bike racer and a far cry from his neo-pro year when he made 22,500 euros.

Men's Health asked Froome whether it was easy for him to stay lean:

"No. I think hard about the quality of the food I'm eating – organic fruit, vegetables and meat wherever possible. It's a common misconception that because we're training five or six hours a day that we can eat what we want and burn it off. It really is a case of watching every little thing you put in your mouth and how it's going to benefit you. Your body really does respond to tweaks then."

In Froome's autobiography, "The Climb," he likens eating right to fidelity:

"I try to go very light in terms of diet. In the mornings I limit myself to just the one bowl of porridge, and normally a two-egg omelette, with no hint of extras on the side. No second helpings, no picking, nothing. If there is a big stage ahead that day I'll try a three-egg omelette, but warily, and I'll mix a small amount of white rice into the porridge ...

"On to the desserts, which no longer contain 'love' as I like to put it. Instead, I'll chew a few pieces of fruit or have a pot of yoghurt. I don't count calories or know the values of most things; I just let my instinct guide me as to what is the right amount to eat. My instinct always says that the right amount is less than I feel like eating. In a previous life I think my instinct lived in a remote monastery. I can think of food, see things in terms of food ... But I just can't eat food. Not like before. It's a fidelity thing."

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