Eat Carbs and Fat for Energy1 of 14
When you're riding on level ground at moderate pace, you primarily burn fat for energy. As you start to work harder, you burn fat but you also burn more glycogen, which comes from carbs. As you ride harder you'll burn more and more glycogen and keep burning fat. By comparison, protein only provides about five percent of your energy.
Limited Glycogen Stores2 of 14
Even the skinniest rider has enough body fat for 100 miles, but not enough glycogen. You can store about 450 grams of glycogen in your muscles, blood stream and liver. This will produce about 1,800 calories of energy, enough energy for only a few hours of hard riding.
Carb Load3 of 14
To be sure your glycogen stores are full, start eating carbs three days before your event. At each meal, cover your plate primarily with carbs and think of protein as a condiment. Remember to drink eight glasses of primarily clear, unsweetened fluids per day. Avoid alcohol. You'll probably gain a little water weight since your body stores water with the glycogen. The weight shouldn't be an alarm. You'll use the extra water during the event.
Pre-Ride Breakfast4 of 14
Eat a good breakfast containing 750 to 1,000 calories a couple of hours before the start of the century. Eat mostly complex carbs with a bit of protein and fat. Try whole-grain cereal with a banana and skim milk or multi-grain toast with low-fat yogurt and berries. Drink a few glasses of fluid (a glass of juice and a cup or two of coffee or tea) and don't worry about the caffeine. It won't cause you to urinate excessively, and by eating several hours in advance you give yourself time to digest the calories and to relieve your bladder before the start. An hour before the ride, eat a snack such as a banana or energy bar.
Don't Bonk5 of 14
Your brain needs fuel, and unlike your muscles, your brain can only metabolize glycogen for energy. If your muscles burn through all of your glycogen stores, you'll bonk and get that awful fuzzy-brained feeling when all you'll want to do is stop. Similarly, when your muscles exhaust all of your glycogen stores, you'll hit the wall and your muscles will feel like lead.
Eat Frequently6 of 14
To avoid bonking or hitting the wall, replenish your limited glycogen stores during the ride by eating primarily carbs. Every hour consume one-half the calories per hour that you're burning. Use the Calorie Estimator to estimate how many calories you'll burn based on the distance, total climbing of the event, body weight and how fast you're riding. If you have trouble remembering to eat, set your computer to beep every 15 minutes.
Eat a Mix of Carbs7 of 14
Research shows that you can digest more carbs (up to 90 grams or 360 calories) per hour if you eat a variety of carbs. Eat a sports product with sucrose and maltodextrin, a bagel and a banana or fruit newtons. On your training rides, experiment with different types of carbohydrates to see what tastes good and agrees with your stomach.
Sports Food Versus Real Food8 of 14
Sports drinks, bars and gels are convenient. However, they don't provide any performance advantage over fruit, peanut butter sandwiches, granola bars or cookies.
Drink to Satisfy Thirst9 of 14
If you start the event well hydrated, you only need to drink when you're thirsty. We used to be taught, "Eat before you are hungry, drink before you are thirsty." The former is still good advice. However, current research indicates that drinking too much can lead to hyponatremia, a fatal condition involving extremely low blood-sodium levels.
Choose What Works for You10 of 14
Test your nutrition during training rides. What tastes good and digests easily varies among riders. Don't just rely on advice from other cyclists, the media or even me. Experiment to find out what works for you.
Nothing New11 of 14
Try to find out from the ride organizers what food and drink will be available at the stops. If they don't provide food and drink that sit well in your stomach, bring your own. Don't try anything new during an event. If you've been eating energy bars, don't grab a brownie at an aid station. If your training rides include a stop for coffee and pastry and then lunch, take advantage of these during your event.
Keep It Simple12 of 14
You'll have a better ride and more fun if you develop and follow your own simple nutrition program rather than getting hung up on too many details. These are just suggestions. Try different combinations of food and drink until you find something that works for you. There is no one recipe for success.
Do You Eat to Ride or Ride to Eat?13 of 14
If you eat in order to fuel a PR, then view stops as aid stations, not as rest stops. Grab what you need and eat and drink on the bike. A two-time winner of the Race Across America once said, "If you aren't on the bike, you aren't going anywhere." If you ride so that you can have fun and enjoy a variety of foods, then stops are social opportunities. It's okay to enjoy the snacks while talking with others.