As far as carbohydrates are concerned, not only is the quantity of carbohydrates we consume important, but also as important—if not more so than the quantity, is the quality of carbohydrates. This brings us to a guide called the Glycemic Index (GI). Is it a very useful tool, or useless information? The answer to that question is a resounding YES! Let us first look at the definition of the glycemic index. It is defined as a guide used to indicate how much a food will increase blood glucose levels relative to pure glucose. Pure glucose, by the way has a glycemic index value of 100. A number from 0 to 100 is assigned to a given food to compare how that particular food raises blood glucose levels compared to 50 grams of pure pharmaceutical grade glucose. The lower the number, the less that particular food resembles pure glucose; the higher the number the more that particular food resembles and acts like pure glucose. In practical terms, the glycemic index is in¬fluenced by the form (liquid or solid) in which the food is eaten, its fiber content, the presence of protein and fat, food-processing and food-preparation methods as we learned in the Executive Nutrition article posted on our website at www.ExerciseAndNutritionWorks.com. The GI was developed as follows: a group of test subjects had their blood glucose levels measured and a 50g dose of pharmaceutical grade glucose was administered. The blood glucose level changes were graphed and the area below the curve was recorded and labeled Area "A.” The same group of people then went through a number of tests where 50g of "X” (rice, bread, yams, pasta, oatmeal, oranges, etc) were administered and their blood glucose response graph and areas were recorded and this area was labeled Area "B.” As a way of comparing the two responses, the researchers decided to divide Area "B” by Area "A” to calculate the percentage that B represents of A; this is how they came up with the glycemic index values. In short, GI describes how 50g of a particular carbohydrate raises blood glucose levels compared to 50g of pure pharmaceutical grade glucose. Here are the problems with these assumptions: 1. Nobody eats rice, bread, yams, pasta, oatmeal, oranges, etc in 50g increments. 2. Nobody eats rice, bread, yams, pasta, oatmeal, oranges, etc by themselves. As noted in the Executive Nutrition article, when combined with protein, and/or fat (as well as fiber), gastric emptying time of carbohydrates changes—it increases, or it takes longer for carbohydrates to "empty” or leave the stomach. When gastric emptying time increases, blood glucose levels do not rise as quickly, changing the blood glucose curve used to determine Area "B.” This change in value for area "B” renders the glycemic index useless unless an individual eats carbohydrates alone (without combining them with protein and/or fat), and in fifty gram increments or portions. The glycemic index is not simply a function of whether the carbohydrate is in a liquid or solid form. An orange has a glycemic index that is almost identical to the value of orange juice. The glycemic index is also not a function of whether the food is a starch (such as pasta) or simple carbohydrate (such as table sugar). For instance, a baked potato has a glycemic in¬dex that is close to the glycemic index for glucose. So, is it a very useful tool or useless information? In reality, it is both. It is a very useful tool in that the latest research shows it to be beneficial to ingest large amounts of pure glucose or any other high glycemic index food 15-20 minutes AFTER a workout. Five hormones are secreted during exercise: growth hormone, epinephrine, norepinephrine, glucagon, and cortisol. These hormones are insulin-blocking hormones—their main job is to make glucose available for exercise by preventing insulin from storing it. If you were to drink a shake or high glucose drink immediately after your workout, these hormones would block insulin secretion and you would not be able to store much of the glucose in your muscle mass as glycogen to replenish what you just used during exercise. By waiting 15 minutes after your workout to drink your high glycemic drink, these hormones "have died out” or decreased in volume and now allow a large insulin secretion to shuttle all that glucose right into your muscle mass to replenish the glycogen you just depleted during your workout. This is the mechanism utilized to also shuttle large amounts of creatine into muscle cells after workouts by combining creatine with a high glycemic food or drink. The secret to unbelievable growth - The Glycemic Index and Insulin If you have been following professional body building over the last ten to fifteen years, you have certainly noticed the increase in size, mass, and thickness of the professional competito
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