Athletes love to obsess about gear ounces, but the most obvious spot to drop pounds is around your gut. "It's not always about losing weight but losing body fat," says San Diego sports nutritionist Matt Fitzgerald, author of Racing Weight. "Getting leaner is a sure way for endurance athletes to improve." The most reliable way to find your ideal race weight and body composition is by tracking your performance over time. This quick-start program will get you in the ballpark.
1. Find your current body-fat percentage. A body-fat scale, like Tanita’s Fitscan Body Composition Monitor, is reasonably accurate and much more convenient than a definitive Dexa scan.
2. Determine your target body-fat percentage. Use your current body-fat percentage and the chart at right to set a realistic goal. For instance, a 35-year-old man with 16 percent body fat might initially shoot for 12 percent. If you’re more than ten percentage points away from your ideal range, split the difference.
3. Calculate your body-fat mass. Multiply your weight by your body-fat percentage. For example, if you weigh 165 pounds: 165 lbs. x 0.16 = 26.4 lbs.
4. Calculate your lean body mass. Subtract your fat mass from your weight: 165 lbs. – 26.4 lbs. = 138.6 lbs.
5. Find your target lean-body-mass percentage. Subtract your target body-fat percentage from 100:
100 – 12 = 88 percent.
6. Calculate your target race weight. Divide your current lean body mass (step 4) by your target lean body mass (step 5): 138.6 ÷ 0.88 = 157.5 lbs.