Part 1: Pre-Competition Fueling

  Nutrition is an integral, though often overlooked, component of an athlete’s training regimen.  Food provides the fuel that allows your body to run down a soccer field or the person in front of you in 5 k race.  Inadequate or improper fueling will limit performance.  While each athlete is as unique as the sport in which he participates, there are some guiding principles that apply to all athletes.  In this three part series, we will provide some guidelines and suggestions for proper fueling before, during, and after games or races.  Keeping these simple concepts in mind will help move you toward an optimal fueling strategy that will allow you to compete at your best.

 Energy from food is stored in the body:

   Our bodies are the ultimate in hybrid vehicles.  We utilize a wide variety of fuels to generate energy for everything from a maximal bench press to an ultra-marathon.  For most team and endurance activities, however, we rely primarily upon carbohydrate and fat for fuel.  Carbohydrate is your body’s preferred source of fuel during moderate to high-intensity exercise and is stored in our muscles and liver in the form of glycogen. Storage space, however, is limited.  Our bodies can only store enough carbohydrate to fuel about 90-100 minutes of moderate to high-intensity effort.  If you are not consuming carbohydrate during sustained exercise, you will eventually deplete your stores and your muscles will be forced to rely primarily on fat.  Even the leanest athlete has enough fat to fuel several marathons but utilizing it requires a great deal of oxygen.  This means that your pace must decrease in order to provide your body with the oxygen necessary to continue to exercise.  Running out of carbohydrate is what endurance athletes refer to as “bonking” or “hitting the wall”.

Carbohydrate Loading:

   The goal prior to competition is to optimize your body’s carbohydrate stores.  Obviously, the amount of fuel that you will need will depend upon the duration and intensity of the event for which you are preparing.  Carbohydrate loading for a 5k race is not necessary because it is a very short event.  Likewise, loading your muscles for an extended bowling tournament is also not necessary as the exercise intensity is very low.  However, if you are preparing to race a half marathon, an Olympic distance triathlon, or play in an all-day soccer tournament, filling your carbohydrate tank is very important.

   In the day or two prior to the event, eat a high carbohydrate diet.  Eight to ten grams of carbohydrate per kilogram body weight will significantly increase your glycogen stores (see calculation below menu).  A sample menu of what this would look like for a 150 pound person is shown below.  For some people, eating this large volume of food may prove difficult.  Under these circumstances, liquids such as juices and smoothies are advantageous because they are high in carbohydrate but are not filling.  It is also a good idea to keep the fiber in your diet to a minimum the day before to reduce your risk of gastrointestinal (GI) discomfort during competition. 

Example (150 pound person*):

 *150 pounds/2.2 pound/kg = 68 kg x 10 grams of carbohydrate / kg = 680 grams carbohydrate
^Removing the mashed potatoes would provide ~8 grams of carbohydrate / kg.

Game/Race Day Nutrition

Assuming you didn’t exercise much the day before your competition, your muscle glycogen stores will remain elevated.  Liver glycogen, however, is used to maintain blood sugar levels at night while you’re sleeping.  Restoring your liver glycogen can be accomplished by consuming 80-100 grams of carbohydrate.  Liquid forms of carbohydrate are easy to tolerate prior to exercise.  If you would rather eat solid food, choose foods that are low in fiber and low in fat as both tend to slow digestion.  White toast or bagels with jam are good choices, along with water or Gatorade to ensure you’re starting the event hydrated.  If your event isn’t until later in the day, you have a bit more time to fuel your body.  In terms of the pre-event meal, however, the same principles apply.  Choose foods low in fat, low in fiber, and high in carbohydrate.  A small amount of protein in this meal can help to stabilize blood glucose levels.

How long before a game or race should you eat?   Individuals vary greatly in their ability to tolerate food prior to exercise but, in general, the closer you are to competition, the less you should eat.  A good range would be 2 – 4 kcal per pound of body weight 1-3 hours prior to exercise.  For a 150 pound person, that would be 300 kcal one hour before or 600 kcal 3 hours before competition.  Ideally, the food should be out of the upper GI tract when exercise begins to reduce the risk of GI discomfort.

Common Foods and their Carbohydrate Content

It is important to provide your body with the fuel that it needs to compete at a high level. Inadequate intake or poor food choices in the 24 – 48 hours before competition will hinder performance. No race car driver would think about arriving at the Indy 500 with an empty tank, though many athletes do just that. The next article in this series will focus on what to eat and drink during competition so that your body doesn’t run out of gas.