Have you signed up for a running or walking event in 2011, such as Race for the Cure 5K or Avon Walk for Breast Cancer? Good for you! A run/walk event is a great way to get in shape, stay fit, and help others at the same time. Smart nutrition is critical to fueling your body and maintaining a positive experience, so heed these five tips from Elisa Zied, MS, RD, CDN, author of Nutrition at your Fingertips (Alpha, 2009).

1. Focus on good carbs. Because carbohydrates are the body's best source of energy--especially for athletes--about 45-65 percent of total caloric intake should come from carbohydrate-rich foods, says Zied. "Carbohydrates provide both quick and long-lasting energy, and our bodies can use them more efficiently than proteins or fats." Healthy sources include oatmeal, whole-wheat pasta, brown rice, fruits, beans, and vegetables.

2. Choose fats wisely. Twenty to 35 percent of a runner’s or walker's diet should come from healthy fats, says Zied. "During exercise, muscles rely on fats for energy after the energy from carbohydrates has been depleted. But limit intake of foods high in saturated or trans fats, or cholesterol, as they can contribute to a host of health problems." Good mono and poly fats, as well as inflammation-fighting omega-3s, are found in cold-water fatty fish, some oils (like olive, canola, and soybean), walnuts, flaxseeds, and tofu, she says.

3. Repair with protein. "The body uses protein to repair tissue damaged during training, and protein-rich foods supply us with much needed energy," says Zied. Make protein about 10-35 percent of a runner’s or walker's daily intake, or one-fourth to one-third of your plate. Rather than saturated-fat and cholesterol-laden meat cuts, choose lean meats and poultry, fish, low-fat dairy products, beans, nuts, and seeds to meet your protein needs.

4. Be smart about supplements. "Vitamins and minerals don’t provide energy, but they are still vital to the health of runners and walkers alike," she says. If you eat a well-balanced diet, you're probably getting most of the nutrients you need; even so, consider supplements to fill in any gaps based on your specific needs and age.

5. Drink (or eat) your water. It can't be said enough: It's critical to stay adequately hydrated, especially before, during, and after your run or walk, says Zied. According to the Institute of Medicine, women should drink about 11 cups a day; men, 16 cups. "Don't use thirst as your guide. If your urine is pale in color, that's one indicator you're adequately hydrated," adds Zied. Keep water on hand at all times to sip throughout the day, and eat water-rich foods, including lettuce, melons, oranges, soup, and yogurt.