A Glossary of Terms

Sport nutrition is a separate category complete with its own unique language. It is loaded with technical terminology and mixed with its own brand of vernacular and slang. It also differs from sport to sport and from country to country, just as the dialect of English also varies between England and America, or from one region of Canada to another.

Athletes respond extremely favorably to anyone who knows their language. You don’t have to play the sport, but if you can speak their language the doors of communication will open wide. Speak someone’s language and a bond instantly forms! The ice is broken and a new friendship is culminated. If I were given three wishes, one of them would be the ability to interpret and speak every language of the world. Remember, no one ever needs to succumb to the tyranny of words as long as they are willing to make the requisite effort to master the language which serves their purpose.

Biological Value

Protein means "to come first." Though recognized as an essential resource for everyone, caution must be applied to its quality, source and method of preparation. Excess cooking denatures protein and reduces its biological value. Biological value (BV) refers to the percentage of nitrogen absorbed and retained by the body. This in turn affects muscle growth, wound healing and recovery. The BV of whey protein is the highest known (104-159), compared to 100 for an egg, 83 for fish or 79 for chicken. All plants proteins, although endowed with other virtuous properties, rank low on the scale of biological value.

Consuming low-quality damaged protein can reduce both performance and life expectancy by increasing free radical production in the body. Commercial sources of animal protein are frequently high in saturated fat, laden with fat-soluble toxins and often contain parasites or harmful microorganisms. Conversely, engineered whey proteins are extremely low in fat and lactose (milk sugar), provide superior amino acid ratios which resist oxidation and enhance immunity by raising antioxidant levels of glutathione.

Nitrogen Balance

Protein supplies our only dietary source of nitrogen, which the body needs to synthesize creatine, niacin, B12 and even our genetic hardware. Scientists compare nitrogen intake to nitrogen excretion (nitrogen balance) to determine if adequate protein from the diet is being obtained.

Prolonged stress and injury, certain disease conditions, infection and increasing exercise volume or intensity causes the body to excrete more nitrogen than usual, confirming the notion that protein is being used at a much faster rate.

If nitrogen excretion exceeds nitrogen intake (negative nitrogen balance) muscle is catabolized (used as a fuel source) to supply the functional needs of the body. This occurs on weight-loss diets which lack sufficient protein and the impetus to maintain and preserve lean mass (resistance training).

If one’s objective is to regain lost muscle or gain new lean tissue, the individual must create a growth impulse through load-bearing exercise and achieve a positive nitrogen balance by consuming adequate high-quality protein.

Cell Volumizing

This term describes the effect of certain nutrients on the water volume inside a muscle cell (intracellular fluid compartment). When muscle cells become swollen with water, an environment conducive to tissue repair and growth is created. Protein breakdown is inhibited and glycogen storage is enhanced. More nitrogen is retained and muscle separation improves. Weight-lifting respondents tend to feel and look "fuller" and generally experience greater physical strength and power.

Creatine monohydrate is the most well known cell volumizing agent. Other adjunctive nutrients which contribute to this effect include glutamine, taurine, manganese, RNA and alanine. They tend to move across the cell membrane by osmosis and function as water attractants or contribute to the enzymatic process associated with cell response and membrane receptor activation.

Glycemic Index

Knowing the glycemic response of food is just as important as knowing its micronutrient content, its caloric value and its acid to alkaline ratio (pH). Successful body composition management relies on this knowledge and for athletes, it’s crucial to performance.

All dietary carbohydrates are not equal, as their rate of digestion and absorption varies. Simple sugars (other than fructose) tend to enter the bloodstream quickly, causing a sharp rise in blood-sugar. This produces an elevated insulin response.

Complex, long-chain and fiber-rich carbohydrates enter the bloodstream more slowly. A moderate rise in blood sugar occurs, causing a moderate insulin response. Both responses are favorable, but with athletic performance in mind, timing is crucial.

The glycemic index of carbohydrates was originally developed for diabetics. Knowing the effect of food on blood sugar is important for monitoring a diabetics glucose (blood sugar) levels. Foods that lead to a slow increase in blood glucose have a low glycemic index. Those that induce a rapid rise in blood sugar have a high glycemic index.

The glycemic index measures the extent to which blood glucose increases after eating a 50g portion of carbohydrate. This increase is then compared to glucose, which is given the value of 100. Knowing the glycemic index of different fruits, vegetables and starchy foods is important because a rapid rise in insulin, except after a workout, can ruin your fat-reducing objectives, increase serum cholesterol levels, encourage the onset of fatigue, intensify joint inflammation and set you up for hyperinsulinemia. Athletes need blood sugar stability. We all do.

Carrots, white potatoes, bananas, bread, rice cakes and white rice cause a rapid rise and fall in blood-sugar. These foods should be avoided before you workout. Pre-workout meals should consist of foods that have a low glycemic index (under 50), such as slow-cooked oats, plain yogurt, green apples, cherries and plums, or a yam/protein combination.

You can reduce the glycemic response of food by combining it with an essential fat or a high quality protein, both of which have low glycemic indexes. This is why I add 2 scoops of whey peptides and 2 T. of hemp or flax seed oil to my morning freshly squeezed grapefruit juice a couple hours before training. Whole grapefruits have a glycemic index of about 26, the juice about 35. I also add 1 tsp. of calcium ascorbate (non-acidic vitamin C powder), 5 grams of L-glutamine and 5 grams of D-Ribose.

Glycemic Index of Selected Whole Foods

Carbohydrate Density (CD)

The carbohydrate density (CD) of a food refers to the digestible carbohydrates present in any given food. This is calculated by subtracting the fiber (F) portion, which is indigestible, from the total carbohydrate (TC) content. Natural carbohydrate-dense foods, such as potatoes, oatmeal, whole grains, beans, starchy vegetables (yams & squash) and many fruits are low in water volume and therefore high in sugar (carbohydrate).

These foods score high on the CD scale, whereas kale, green beans, tomatoes and peaches score low. 100g of broccoli for instance contains 25 calories, compared to 100g of white or whole grain flour which contains about 400 calories. Broccoli is mostly water, whereas flour is mostly sugar. But they are both high-carbohydrate foods.

Every plant on this earth consists mainly of carbohydrates and in some cases plenty of fat (olives & avocadoes). Although lentils and legumes have a reputation for their higher than average protein content (18-22%) the vast majority of their calories come from carbs, not protein. So they are NOT high-protein foods. The biological value of ALL plants is also relatively low (<75). The only true high protein foods in nature are low-fat wild tissue proteins, such as venison, moose, caribou and most fish. To qualify as a high-protein food, the majority of calories present must be derived from protein. Commercial meats are actually high-fat foods, because domesticated animals are typically fed grains (instead of green grass) and lack physical activity.

The amount of insulin your body produces after eating food depends on the density of carbohydrates present and the glycemic index of that food. The more carbs you eat the more insulin your body will produce. So even though naturally occurring starchy vegetables and whole grains are more nutritious than refined carbs - such as pasta, white bread and potato chips - they can still cause blood sugar and insulin to elevate beyond acceptable levels. And unless you are lean and/or extremely active, eating a lot of starchy foods can get you fat, keep you fat and/or encourage the development of Syndrome X. If you can't let go of the most common starch staples, such as bread, bagels, muffins or pasta, the best time to consume them is post-workout earlier in the day. The worst time is in the evening when you're generally less active.

Carbohydrate Density of Selected Foods

CD = Carbohydrate Density TC = Total Carbohydrate F = Fiber

Glycogen

Glycogen is an animal polysaccharide, which is a type of glucose polymer or complex carbohydrate. Polysaccharides contain at least 3 sugar molecules linked together, but more often they contain hundreds or thousands. Starch and fiber are two common forms of plant polysaccharides which are resistant to human digestion.

Maltodextrin is a complex carb derived from corn and grain starch. Many varieties exist of which most demonstrate a high-glycemic effect, even though they are "complex".

Glycogen is kind of like a potato starch. It is stored in our muscles and liver (400-600 grams) and represents a major source of carbohydrate energy for active muscles during anaerobic and high-volume exercise.

After we burn our way through the cell’s small supply of stored ATP and creatine phosphate, glycogen comes to the rescue. But without sufficient oxygen, lactic acid is produced as a by-product of its metabolism, causing acidosis.

Glycogen is synthesized and built from glucose molecules in our blood, which comes either from eating carbohydrates directly or from derivatives of fat (glycerol) and the carbon skeleton of some amino acids obtained from within the body (gluconeogenesis). Dietary carbohydrates are not classified as essential nutrients.

Photo by Moustapha Youssouf from Burst

As always...stay well and live free! Dr.C