By James Giordano, Ph.D.
Your training is going pretty well. You’re hitting it hard four or five days a week, but you’re still not quite “at the peak.” Sooner or later, it will dawn on you, “Am I training to eat, or eating to train?”
Initially, a lot of people work out to knock off some extra weight and burn calories (the “train to eat” syndrome). But as the focus shifts to improving your training, most athletes come to recognize the importance of a nutritional program for performance. This is when “eating to train” becomes a key part of the exercise regimen.
For many people, the word “diet” conjures up images of cottage cheese and pieces of lettuce. However, unless your athletic workouts consist of hopping around on your paws and wiggling a set of large ears, this is not the diet you need. A better concept is adopting an “eating regimen” geared to the type of training that you do. Runners’ nutritional needs differ from weightlifters’ needs for performance enhancement, and if you cross-train, your dietary basics need to support all facets of your training.
Providing a menu is not feasible because your specific eating schedule is uniquely dependent on job and lifestyle, and individual palates differ. Instead, I will give you basic information on the three primary nutrients—protein, carbohydrates and fats—and then provide fundamentals for the nutritional aspects of athletic training for specific types of events.
Proteins
Protein’s main role is to provide and maintain the basic structure of most body tissue, and it is also used as an energy source. It is a nutritional requirement. Actually, humans do not need lots of protein per se, but rather a supply of the amino acids the whole proteins provide. Humans can derive protein from both animal and plant sources.
Animal proteins tend to be more “complete” than plant proteins. In other words, plant proteins exist in lower concentrations and have lesser amounts of certain amino acids. That’s not to say that vegetarians are protein-deficient. With some creative dietary planning, a vegetarian can mix and match plant protein sources to get a full complement of nutritional amino acids. Proteins not only provide amino acids, but they also provide nitrogen. Nitrogen balance is critical to tissue growth and repair, particularly muscle. This condition is known as anabolism.
Studies have shown that nitrogen balance drops when muscle tissue is stressed, and they have indicated that while the required daily allowance (RDA) for protein is about 0.5-1.0 grams per kilograms of body weight, this may be sufficient for high-performance athletes.
Debates on “high-protein” diets (i.e., Atkins, Sugar Busters, etc.) and athletic performance still surface. The fact is that protein is required as an amino source, and the bulk of research seems to show that athletes (both strength and endurance) may need somewhat more protein than RDA. This is particularly true for strength athletes (e.g., weightlifters, body builders, wrestlers, rugby players, etc.) How much more? Studies have suggested 2-2.5 grams per kilogram of body weight may be a better “ballpark” figure.
This isn’t a call to go to a pure protein diet, but it does offer some interesting findings. Another notable fact is that protein can raise the metabolism during digestion more than fats or carbohydrates. This effect, called specific dynamic energy, reflects systemic reaction to food digestion. Protein cranks up the metabolism about 15-30 percent, while fats and carbohydrates only boost it 4-6 percent. This may be due to the breakdown and reshuffling of amino acids, but whatever the cause, the effect is beneficial.
A note of caution: Evidence exists that overdoing protein can overload your liver (the liver converts proteins) and kidneys (that break down and excrete excess amino acids).
Water is vital to assist the body in its metabolism of protein. So, if you’re increasing your protein intake, drink lots of water. One last note on protein: Your system can only effectively use 15-30 grams of protein at one shot.
The trick is to take in your 15-30 grams through many (i.e., 4-5) smaller to mid-sized meals. You can achieve this with about 6-8 ounces of tuna, chicken or turkey or about 6-8 egg whites. On the vegetarian platter, two cups of beans (such as red kidneys or garbanzos) will do the job.
CarbohydratesWhile protein serves as a primary source for tissue growth, carbohydrates provide a primary source of energy. There are three basic types of carbohydrates: monosaccharides, like glucose; disaccharides, like sucrose and maltose; and the polysaccharides, complex carbohydrates coming from starches found in plants. Your body breaks down polysaccharides and disaccharides to glucose, which is used for cellular energy production.
Complex carbohydrates not immediately converted and used as glucose are transformed in the liver to a mid-product and finally to glycogen. Glycogen can be stored in the liver and pulled into muscle tissue, where it is used as a fuel reserve. In fact, a 150-pound man may store up to 75 grams of glycogen in the liver and be able to pull 300 grams into muscle tissue for use. During intense or durational exercise, muscle glycogen becomes the prime supplier of energy production.
You are probably thinking, “Great, I’ll chow down on the carbs and be able to leap tall buildings in a single bound!” Wait a minute. Excess carbs (those that do not refuel depleted muscles or are stored in the liver) can be converted to fatty acids and stored in adipose (fat) tissue. The fat cells swell with their newfound fatty acids and body fat will develop and grow.
Therefore, the key is to “carb-up” as necessary for how you use your carbs. High to moderate aerobic exercise does a pretty good job of putting a dent into your muscles’ carb account. This is particularly true if endurance factors come into the picture. Remember, duration is a key in carb utilization. Runners, swimmers, cyclists and athletes performing sustained workloads burn off muscle glycogen like a New Mexico brush fire. They need to “carb-up” to refuel their depleted glycogen stores.
If you‘re training in a predominately aerobic sport, carb-up significantly. Think “mostly carbs and some proteins.” If you’re predominately an anaerobic, power athlete, think “balanced protein/carb intake, going a little heavier on the protein.”
If all the research performed to date is on target, you’ll probably do well to take in more protein than carbs (spare the extra pasta and have a few more portions of the grilled chicken). But, if you remove carbohydrates from your diet, you’ll be fatigued, irritable and actually begin to feel ill. You need some carbs to digest protein, and carbs hold three times their weight in water, which is a systemic coolant and provides “fullness” to muscle (helping both the strength of contraction and providing “the pump”).
Fats
Fats are necessary for physiologic function. They protect and insulate body structures and organs and serve as a source of long-term stored energy. Body fat is mainly derived from the diet. This fat is a carrier for the fat-soluble vitamins A, D, E and K.
But the dietary need for fat can be met by as little as 5-15 grams daily. The bodily demand for any excess can be pulled from carbohydrate or protein metabolism. Fat is not the absolute villain; too much fat is.
If you’re sticking to a low-fat eating regimen (fish, white meat fowl, veggies, fruit and grains—either baked, broiled or boiled but not fried), you’ll get plenty of intrinsic fat that comes from these low-fat sources. Start taking in extra fat (fatty meats, rich sauces and gravies, whole dairy products), and fat metabolism will deposit these fats in adipose tissue or break them down into component lipids. The lipids are then carried in the bloodstream, which can deposit them the heart and muscles, contributing to rises in cholesterol and increased plaque in your blood vessels).
Fat has almost double the calories per gram as protein or carbohydrates. While that’s a nifty trick for storing potential thermodynamic energy for insulation and protection, it is only effective if (a) you’re periodically going on a nomadic trek and fasting; or (b) you’re in a very, very cold environment. Unless you’re an Eskimo (Innuit Eskimos maintain a high-fat diet because they need it), it doesn’t make any health sense to take in extra fat.
Basically, there are saturated fats that come from animal sources and appear to lead to increased serum lipids and higher cholesterol levels. These conditions have been shown to contribute to the development of arterial disease.
Unsaturated fats come from plant vegetable sources that include corn, soy, safflower and peanut oils. There are two kinds of unsaturated fats, mono-unsaturated and polyunsaturated. Mono-unsaturated fats have little total effect on serum cholesterol, and certain poly-unsaturated fats may have been shown to actually reduce serum cholesterol levels.
Be sensible. From this information, you should be able to determine what should go on your training table: