Carbs: The Anabolic Nutrient
Carbohydrates can help you pack on muscle — or bodyfat — depending on when, what and how much you eat. Here’s what carbophobes and carboholics need to know about this important macronutrient for optimal physique gains.
These sugars are formed by the chemical combination of two monosaccharides. They also taste sweet and have a relatively fast absorption rate. Common disaccharides include lactose (glucose-galactose or milk sugar), sucrose (glucose-fructose) and maltose (glucose-glucose). Maltose elevates blood sugar very rapidly (in fact, it does so faster than glucose) and sucrose only moderately increases blood sugar, whereas lactose digests slowly and has a small impact on blood sugar.
These are carbohydrates formed by bonding several chains of monosaccharides and/or disaccharides. This form is commonly known as complex carbohydrates and includes starch, cellulose and glycogen. Starches are made up of multiple glucose units bonded together and are “plant sugars” produced by all green plants as an energy source. Common sources of starch are potatoes, wheat, corn and rice. Cellulose forms the structural components in plants and is relatively indigestible in humans — fiber is a form of cellulose. Most starches are considered medium- to slow-digesting, however, exceptions exist, one of which is waxy maize. The reason waxy maize absorbs so quickly is that it’s a modified high-molecular-weight cornstarch that has low osmolality, which enables it to bypass the stomach and get absorbed in the small intestines (causing a rapid rise in blood glucose).
The Glycemic Index
A common misconception is that all simple carbohydrates are fast sugars and all complex carbohydrates are slow sugars. This is definitely not the case; in fact, some complex carbohydrates (like maltodextrin) raise blood sugar and insulin levels rapidly, whereas a simple sugar like fructose has minimal impact on blood glucose. This variation is exactly why the glycemic index was created — to help you understand how different carbohydrate sources impact blood sugar. Using this tool is quite simple — all carbohydrate foods are ranked on a scale relative to glucose (a fast sugar, rated 100). Anything lower than 100 impacts blood sugar less than glucose and anything higher impacts it to a greater degree. For reliable glycemic index information or to search the database for specific food GI calculations, visit www.glycemicindex.com. One important point to note is that fats, fiber and, in some cases, proteins can significantly slow the speed at which fast (high-glycemic index) carbs elevate blood glucose. Keep this in mind when employing the strategies outlined next.
Carb-Based Muscle-Building Strategy
There’s an abundance of scientific research supporting carbohydrate supplementation for muscle building. After exercise, muscle glycogen stores are depleted and insulin sensitivity is greatly increased, thus providing the perfect opportunity to spike insulin by ingesting fast carbohydrates like dextrose, maltodextrin or waxy maize. Not only does the boost in insulin increase glycogen repletion, but it also serves to carry amino acids and nutrients into damaged muscle cells. Several studies indicate that post-training carbohydrate and protein supplements boost the anabolic response, augment recovery and promote increased gains in lean mass.