Whether you’re going for a P.R. or prefer to smell the roses, nutritional factors will be major determinants of how successfully you meet your goals for a century, brevet, or double century.

by Susan I. Barr, PhD, RDN

Susan Barr, is on the faculty of University of British Columbia in nutrition. She is a veteran of Paris-Brest-Paris, the Rocky Mountain 1200 and many PAC Tours and Pacific Crest Tours.


Optimizing your performance from the nutrition perspective involves a three-pronged approach:
1) glycogen supercompensation (carbohydrate loading) the week before the event;
2) eating a meal the morning of the event; and
3) consuming foods and fluids during the event itself. Here’s a countdown to help your preparation.

Months in advance
• Contact the event organizers and find out what foods and beverages (if any) will be provided at checkpoints. If you haven’t used the sports drink that’s being provided, start using it in your training rides.
• Eating and drinking while riding moderately hard are learned behaviors and need to be practiced. You also need to learn what you tolerate best on long rides. Determine the rates of fluid and carbohydrate intake you’ll need to maintain during the ride (see below), and aim for these intakes during training rides. If you have trouble remembering to eat and drink at regular intervals, set your watch to go off every 15-20 minutes. Although it may infuriate your training partners, it will help you learn to take in fluids and energy regularly.

The week before
• Glycogen supercompensation, or carbohydrate loading, helps prolong endurance in events lasting over two hours. Estimates are that it can move the wall about 20% farther down the road. Clearly, it won’t see you through a double, but it provides a good foundation for the two other strategies.
• To effectively carb-load, taper your training during the week before the event, ending with either a rest day or an easy spin. This will allow dietary carbohydrate to be stored as muscle glycogen rather than being used as a fuel for cycling.
• In conjunction with backing off the mileage, you need to increase carbohydrate intake for the last 3-4 days of the week—aim for 8-10 grams of carbohydrate per kilogram body weight.
• You’ll know things are working if you gain some weight. Each gram of glycogen is stored with 3 grams of water, so filling glycogen stores with an additional 300-500 grams should lead to a weight gain of up to 2 kg. Don’t worry—most of this additional weight is water, and will actually be helpful during the ride.

A few days before
• Optimal hydration is critical to endurance performance and can’t be accomplished by drinking large amounts of fluid the morning of the event. The American College of Sports Medicine recommends increasing fluid above usual levels for at least 24 hours before an event.
• Aim for 2-3 water bottles of fluid on top of your normal intake. If you use caffeinated beverages, drink at least an equal volume of a non-caffeinated beverage for each cup of caffeine.

The morning of the ride
• During an overnight fast, liver glycogen is used to maintain blood glucose levels. If liver glycogen isn’t restored (by eating) before starting to ride, hypoglycemia can develop and will contribute to premature exhaustion.
• General guidelines for pre-event meals include the following:
1. Use foods that are familiar and that you know you’ll tolerate. Liquid meal replacement beverages may be useful for those who don’t tolerate solid foods.
2. The meal should be relatively low in fat so that stomach emptying isn’t delayed.
3. It should provide carbohydrate (about 50 grams for each hour before the ride that the meal is eaten—so 100 grams for a meal two hours before, or 150 grams for a meal 3 hours before). As an example, eating a banana and a large bagel with jam will provide close to 100 grams of carbohydrate. Having a meal will mean getting up early—but it’s worth it in terms of helping performance. Also, note that this guideline is intended to allow enough time for the food to leave the stomach, so you won’t start the ride feeling overly full. If you’re not planning to ride hard, meals can be eaten in closer proximity to the start.
4. It should provide fluid. The American College of Sports Medicine recommends drinking 500 ml (about a water bottle) two hours before starting. This will allow enough time to excrete any excess fluid. If you can’t survive without coffee, by all means have some—but be sure to include a non-caffeinated source of fluid as well.

During the ride
• Begin to take in fluid and energy immediately. If you allow a deficit to develop, it’s almost impossible to recover. You know the drill. “Eat before you’re hungry; drink before you’re thirsty”.
• How much fluid? Ideally, fluid intake should match sweat losses. (This should be assessed before the ride by weighing yourself nude before and after a 2-3 hour training ride. The difference, to which you add the weight of any fluids consumed, represents your total sweat loss. Divide by the length of your training ride to obtain an hourly rate.)
• How much energy? You need a minimum of 0.6 grams of carbohydrate per kilogram body weight per hour, or 0.3 grams per pound of body weight (30-60 grams per hour for most people). This won’t meet your energy needs completely, but that’s not a serious issue for a one-day event. It will help sustain performance.
• What form of energy? Solids (real food or energy bars), liquids and gels all work, so it’s your choice. If it tastes good to you, chances are that you’ll use it on a more regular basis. Some cyclists find solids are difficult to eat while riding moderately hard, and sport drinks containing 6-8% carbohydrate (gms / ml) have the advantage of meeting fluid and energy needs at the same time. A standard water bottle of sport drink provides about 37-50 grams and a large bottle about 45-60 grams. But after 8-10 hours, sports drinks may no longer be appealing, so getting some variety throughout the ride is advisable. Checkpoints are a good time to take in some solid food, if you plan to stop at them.
• Have fun! (and don’t fall)!