The Plan: No professional cyclists, not even Lance, stay at their Tour de France weight all year. They aim to be as light and as powerful as possible for three weeks in July, and after that they move back up to a healthier and more sustainable weight. What Lance and I wanted to avoid, however, was the big weight fluctuation (18-26 pounds) typical of pro cyclists. I wanted his training efforts to improve his power output and make his aerobic engine stronger. Using training hours to merely burn calories and lose weight is a waste of valuable time.

I looked at the ways Lance’s training changed during the year, and then designed a nutrition program that matched the calorie, nutrient, and training demands of each segment of the year. The results were dramatic. Between 2002 and 2005, his weight has fluctuated only about 9 pounds up and down, yet he has not had to go to the extremes of weighing his food or depriving himself of meals or snacks. We have not had to spend time thinking about weight loss, either. That has provided more time to concentrate on performance.

The plan is relatively simple, and works for any active individual. During the fall and winter, the intensity and weekly duration of Lance’s training are relatively low. He is exercising, but it’s mostly moderate-intensity aerobic conditioning. To fuel this level of training, he doesn’t need as many calories as he does at the height of the racing season.

Not only does he consume less food during this period, he also alters the nutrient balance. During the height of the season, more than 70 percent of his calories may come from carbohydrates because he needs the fast-burning fuel to power his aerobic and anaerobic energy systems. During the fall and winter, we increase the percentage of protein in his nutrition program and reduce the carbohydrate contribution to 60 percent to 65 percent. This may seem minor, but when it’s combined with the overall caloric reduction, the two make a big difference in calories and body weight.

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As his training intensity and volume increase through the spring, we increase his caloric intake and the percentage of calories coming from carbohydrate. The aerobic engine can burn a mixture of carbohydrate, protein, and fat, but the anaerobic system that kicks in to contribute additional energy for high-intensity efforts burns only carbohydrate.

My first priority is to make sure Lance has the fuel and nutrients he needs to perform. I look at the demands of his training and lifestyle and use that information to design his nutrition program. It’s an idea with a lot of potential. You’d be shocked to discover how much more you can accomplish when you don’t have to spend time thinking about body weight.