As an Olympic trainer and a former competitive cyclist, Carmichael, the founder of Carmichael Training Systems, has learned that athletes need to match their nutritional intake to the demands of their training in order to achieve peak performance. In his new book, Food for Fitness: Eat Right to Train Right, Carmichael applies his nutritional principles to all types of athletes, particularly runners.
According to Carmichael, runners need to take a holistic approach to eating and training. "Diet and training are so closely intertwined, they can't be separated," he says. Runners' diets, therefore, need to evolve throughout the year to correspond with particular workouts. Essentially, Carmichael takes the training technique known as periodization (you break your training year into "periods" with different goals, then concentrate on specific training) and extends it to the training table.
The concept of periodization naturally translates to nutrition, because the amount of energy you burn changes as you go through weeks, months, and a full year of training. If you're eating the same number of calories all year, there is most likely a portion of the year when you're eating more food than you need. Likewise, there will be times when your training burns more calories and demands more nutrients than you are consuming. So just as your training focuses on different goals in different months of the year, you need to make sure you're eating enough food and the right kinds of foods to support your workouts.
But it isn't as simple as just eating an extra granola bar or two when you're running longer or harder. "Carbohydrates, proteins, and fats are tied together and linked to how you perform," says Carmichael. So on top of eating more calories as your training intensifies, the ratio of carbohydrates to fats to proteins in your diet needs to change as well. "If you are training for a half-marathon, for example, you need a greater percentage of carbohydrates in your diet than if you're just running for fitness," he explains.
Like Lance Armstrong, when you're at the peak of your training, it's important to increase the percentage of carbs in your diet from about 60 to 70 percent to ensure you're giving your body enough fuel to enhance your workouts.
Not surprisingly, Carmichael cautions runners about popular low-carb diets. Slashing carbs can negatively affect a runner's health and performance. This is because carbohydrates are the body's high-octane fuel--the fuel it relies on for speed and power. Cutting carbs from your diet leads to depleted stores of glycogen (the form carbs take when stored in the body). Training in a glycogen-depleted state causes the body to struggle to maintain even low-intensity exercise, making it difficult to improve fitness.