7 Steps to Prevent "The Bonk"
1. Practice race-day nutrition during training. Take this time to learn what works for you and what doesn't.
2. Consume a carbohydrate-rich snack or meal 3 to 4 hours before exercise. Include small amounts of protein and items low in fat and fiber to ensure optimal digestion.
Try a turkey sandwich with pretzels and an apple or plain nonfat yogurt with fruit and low fiber cereal.
More: Healthy Carbs for Endurance Athletes
3. Eat a sports gel, chew or bar or piece of fruit 30 to 60 minutes before exercise. Try this before race-day—some athletes can't tolerate anything this close to training or competition. Note that the closer you get to exercise the smaller your meals should be.
4. Practice proper hydration daily by drinking water consistently throughout the day.
5. Consume adequate fluids during exercise to replace sweat loss. During prolonged exercise (90 minutes or more), the proper balance and timing of fluid, carbohydrate and electrolytes is essential to avoid bonking. Try a sports drink that contains carbohydrate and electrolytes. Or, choose carbohydrate-rich foods that are easy to digest like a banana, bread with jam, sports gels or chews, or small bite-sized pieces of sports bar. Aim for about 30 grams of carbohydrate per hour.
More: Best Race Foods for Runners
6. Start your nutrition recovery 15 to 60 minutes after exercise. Try a smoothie made with yogurt and frozen berries or graham crackers with peanut butter and a banana with chocolate milk.
7. Replace muscle fuel at each meal with carbohydrates, while including some protein to aid in repair of damaged muscle tissue, especially in your post-workout meal. Try a stir-fry with chicken, broccoli, bell peppers, carrots and onions over brown rice or pasta with tomato sauce, turkey meatballs, a small roll and spinach salad.
There's not one tactic that will prevent the dreaded "bonk." However, if you practice proper nutrition everyday, you reduce your chances dramatically. If necessary, talk with a sports nutritionist to create an individualized plan based on your training and competition schedule.
More: 3 Tips to Determine Your Training Food Schedule
Learn more in the nutrition guide.