Training for Climbing, 2nd: The Definitive Guide to Improving Your Performance (How To Climb Series)

eliminating just a handful of killer items like french fries, fried meats, snack cakes and muffins, salty snacks (buy baked chips and crackers instead), and any highly processed food designed for maximum shelf life (no doubt, high in hydrogenated oils).

Carbohydrates
     
    Although fat and protein can be used to provide energy, carbohydrate is the most efficient and effective source of energy for the muscles and brain. A high-carbohydrate diet is also important for athletes due to its protein-sparing effect. If you do not consume enough carbohydrates to meet your energy needs, muscle protein will be broken down for energy—the last thing any strength or power athlete would ever want! Consequently, the popular low-carbohydrate diets (Atkins, Zone, Ketogenic, and so forth) are inappropriate for most active climbers.
    Carbohydrates come in two forms: sugars and starches. The sugar foods include fruit, sugar, soda pop, jam, honey, and molasses, while common starches are breads, rice, cereals, and pasta. Because these are the best sources of energy for high-intensity training and climbing, I’m sure you are already consuming plentiful amounts of these foods. Not all carbohydrates are created equal, however: Different carbohydrates release sugar into the bloodstream at different rates. The very best athletes know how to leverage this information to maintain stable energy throughout the day and to significantly increase the rate of recovery after a hard workout or day of climbing. If you are serious about climbing better, this subject should be of great interest to you. Enter the glycemic index.
GLYCEMIC INDEX
     
    Historically, nutritionists classified carbohydrates only into the two basic groups of simple carbohydrates (sugars) and complex carbohydrates (starches). Simple sugars were said to produce a rapid rise in blood sugar and quick energy, while complex carbohydrates were said to provide slow, steady energy. Although this concept holds true in general, recent studies have found that there is a large variability in the rise in blood sugar following the ingestion of various foods from both the sugar and starch groups.
    To investigate and more accurately classify the metabolism of carbohydrates, researchers developed the glycemic index (GI)—a powerful nutritional tool I first introduced to climbers in my 1994 book Flash Training. This index determines how the ingestion of a particular food affects blood sugar levels in comparison with the ingestion of straight glucose. Consumption of high-GI foods causes a rapid increase in blood sugar and a large insulin response. Low-GI foods produce more subtle changes. Climbers can use knowledge of the glycemic index to control energy levels and to speed recovery after a workout. Here’s how.
    Stable insulin levels are optimal for long-duration stop-and-go activities such as all-day climbing and long training sessions. Experts also agree that a steady insulin curve promotes muscle growth and discourages fat storage. This makes low- to medium-GI foods preferable for climbers in most situations. High-GI foods produce large swings in blood sugar and an insulin spike. One minute you are jonesing to crank another hard route and the next you’re yawning and feeling strangely weak.
    Figuring the glycemic index of certain foods is more difficult than it might seem at first. For instance, most foods classified as simple carbohydrates (cereal, candy, some fruit juices) are high-GI foods. However, so are potatoes, white rice, bread, and bagels—all considered complex carbohydrates. Low-GI foods include vegetables, whole grains, brown rice, and milk (see table 9.2).
    As a general rule, the more processed and easily digestible a food, the higher its glycemic index (for instance, liquids have a higher index than similar food solids). High-fiber foods tend to elicit a slow insulin response and have a relatively low GI. Finally, foods containing some protein and fat along with carbohydrates come in lower on the scale.
    This last piece of information is useful if you don’t have the gumption to memorize and use this index. Consuming some protein and fat during each of your carbohydrate feedings serves to moderate the overall glycemic response of the meal. So for a long day at the crags, select a sports drink that contains some protein and pack mainly balanced-type energy bars (those containing nearly equal amounts of calories from protein, carbohydrate, and fat).
    The one good time to