Have you ever wondered what to eat to maximize your physical activity performance? Nancy Clark's Food Guide for New Runners is the latest book by Nancy Clark, MS, RD, a dietitian/nutritionist/author who specializes in sports nutrition. Clark offers great tips for pre- and post-run snacks and meals, and some yummy yet nutritious recipes to help you correctly fuel your body for exercise.

In her book, Clark advises new runners striving to lose weight to eat just a little bit less; that is, she warns against cutting out so many calories that you get too hungry and blow your eating plan.

For those athletes/exercisers curious about how many calories their bodies need now that they are more active, she details how to create a daily "calorie budget," or meal plan:

1. First, add a "0" to your weight in pounds.
2. To accurately reflect your exercise routine, add an "activity factor" that indicates the amount of exercise you usually get each day.
3. If you're sedentary, add 30 percent to 40 percent of the weight-plus-zero number in no. 1.
4. If you're moderately active, add 50 percent, or one-half, of that number.
5. If you're very active, add 60 percent to 70 percent.

Thus, a 200-pound man would need about 2,000 calories (200 with a 0 tacked on to the end) just to meet the body's most basic requirements. Then, if he's moderately active, he would have to add a 50-percent "activity factor" to maintain his weight (in this case, one-half of his original 2,000, or 1,000 additional calories), for a total of 3,000 calories a day.

For weight loss, Clark advises cutting back your calories only a little, by about 200-300 calories a day. This should, in theory, result in a half-pound-a-week loss, but without making you feel so deprived that you slide into rebound eating. She also recommends splitting this caloric "budget" evenly throughout the day, so that you don't eat a heavy meal at night. This will even allow you to wake up feeling a little hungry in the morning.

Now I'll mention a few of my own tips for those who exercise regularly:

• Use a pedometer to track your progress (2,000 steps is about a mile, and 10,000 steps or more a day is considered "active").
• Get an exercise buddy. I have a walking buddy, and can't say enough about how this boosts the accountability factor.
• Make sure you're drinking enough fluids before, during, and after your workout. Aim to have clear urine, which indicates that you're getting enough fluids.
• Weigh yourself before and after a workout and drink 16 ounces of fluid for every pound you lose during it.
• Don't forget to breath. Proper breath control can make a big difference in how you feel, and could literally help you go the distance!
• Consider trying yoga or breathing work or both to supplement your running/aerobic work.

You might also want to check out Clark's other books for cyclists and marathoners, as well as her classic Nancy Clark's Sports Nutrition Guidebook, Fourth Edition.