By Lauren Jacobsen
Carbohydrates are often given a bad rap in any diet that focuses on burning fat. But the truth is that we need carbs, even when we are trying to get leaner. If protein is the brick, carbs are the mortar that helps build the foundation for a muscular and lean body. While protein helps build and maintain muscles, carbohydrates provide the body with a source of energy to fuel muscles during workouts and replenish muscle energy stores after a workout. They play a role in cell volumization and can help preserve lean muscle tissue, by preferentially acting as a source of fuel over muscle. The pathways that carbohydrates affect are so vital to energy, endurance, and muscle growth that there is even a supplement category dedicated to them.
Supplementing with carbohydrates before, during, and after a workout can deliver a steady supply of glucose through the blood stream to hard-working muscles while elevating the most anabolic hormone we need for muscle growth — insulin. They can help keep performance up, protein synthesis turned on, and reduce recovery time. At one point, carbohydrate supplements were very simple formulations comprised of just simple sugars, but they have now taken on new complex designer structures, formulated for faster absorption and even better results.
Complex and Simple — What’s the Difference?
When it comes to carbohydrates, there really are only two divisions — complex and simple carbs. Complex carbohydrates are made of multiple chains of carbohydrates and are termed polysaccharides; they are formed when many chains of simple carbohydrates are bonded together. Complex carbs provide long-term energy because they need to be broken down by the body before they can be fully utilized. Simple carbohydrates are the most basic form of carbohydrates: they are single-unit structures known as monosaccharides or disaccharides, which are two single units bonded together. The simplest carbohydrate is glucose, while dextrose is two glucose molecules bonded together.
Carbohydrates and Muscle Growth
When we eat carbohydrates, they are broken down by specific enzymes in the body into their simplest form — monosaccharide or glucose — before they can be fully utilized. Once broken down, blood sugar levels rise, causing the release of the anabolic shuttling hormone insulin in the blood. Insulin has one job to do: bring back balance to glucose levels by binding and shuttling glucose and other important nutrients to the muscle or fat tissue for uptake and storage. Once taken up by the cells, glucose is either used to generate adenosine triphosphate (ATP) or energy, stored as glycogen in muscles, or is converted to triglycerides and stored in fat for later use. Every cell in the body stores and uses energy through ATP synthesis and production, which fuels protein synthesis or muscle building, muscle contraction, metabolism, and the transport of nutrients.
Therefore, immediately following a workout, the best option for maximizing muscle glycogen re-uptake is to go straight for the simple carbohydrates, to replace lost glycogen in the muscle, and to stimulate the release of insulin. Simple carbohydrates, when consumed in a 2:1 ratio of carbs to protein, have been shown to help stimulate muscle building and increase muscle glycogen uptake faster. While the type of protein is key, so is the carb source!
The Obvious Choice: Glucose and Dextrose
In terms of replenishing muscle carbohydrate loss and sustaining energy levels, you may think supplementing with glucose or dextrose makes the most sense, but it doesn’t. Glucose and dextrose are slowly absorbed by the stomach, despite their ability to quickly increase insulin once in the blood stream. The small intestine is regulated by special receptors called osmoreceptors, which sense the concentration of stomach contents as they exit the stomach, controlling the rate of gastric emptying. If these osmoreceptors sense that the contents exiting the stomach have a high osmolarity, gastric emptying is delayed, which is the main problem with simple sugars like dextrose and glucose. These types of sugars have high osmolarity and a low molecular weight, which holds up gastric emptying into the small intestine where they are actually absorbed by the small intestine into the blood stream. This action delays insulin release and delivery of glucose and other essential nutrients to the muscles. In addition, it should be noted that even once glucose enters the blood stream via the small intestines, blood glucose levels are not sustainable. Insulin does a very good job at shuttling glucose to muscles, thereby decreasing blood glucose levels almost as soon as it is released. You can continue to sip simple carbohydrates throughout your workout, to help keep your energy levels up, or you can try using a designer carbohydrate that delivers better results.
A Better Choice: Waxy Starches (Amylopectin)
Waxy starches, also known as amylopectin, are carbohydrates derived from various sources, such as rice, barley, and maize. Waxy starches are considered high-molecular-weight glucose polymers — basically hundreds to thousands of glucose molecules that have been linked together. Because of their unique structure, in a solution there are many more molecules available per volume, which means they have low osmolarity rates. When the concentration is higher, the gastric emptying will be faster, in order to restore balance to the stomach concentration. Now, although waxy starches are removed faster, they are still large molecules that need to be broken down into simple glucose molecules before they can be fully utilized by the body.
The Next Generation: Highly Branched Cyclic Dextrins
Highly branched cyclic dextrins (HBCDs) are synthetically produced homopolysaccharides made from the starch isolated from barley, corn, potatoes, or rice. HBCDs have low osmolarity and high molecular weights — this unique structure allows for an even faster transit time versus other simple sugars. Unlike waxy starch, HBCDs are not arranged in linear structures. By changing the structure of the amylopectin through enzymatic processes, this increases the extent of branching and cross-linking and creates unique cyclic structures of branched linked units. Unlike linear chains, the cyclic structures allow for greater access of digestive enzymes that can break apart the bonds faster, passing through the digestive system quicker and providing a sustained release of glucose to the body. In a recent study, research in humans showed that a drink containing a 10-per cent solution of branched-chain cyclic dextrin accelerated stomach emptying much more rapidly versus a drink containing 10-per cent maltodextrin.
On the market today, there are many patented HBCDs that use specific enzymatic methods to produce a unique formula. Although the methods and exact structures may vary slightly, they all have similar properties in that they all have low osmolarity and have high molecular weights.
A unique patented structure of fractionated barley amylopectin has been shown in university studies to empty the stomach up to 2.3 times faster than maltodextrin and simple sugars. It has also been shown to replenish muscle glycogen 1.7 times faster and is 1.8 times faster at increasing insulin response versus maltodextrin and sugars after intense, exhaustive exercise. Lastly, this unique HBCD was also found to increase post-workout performance, increasing maximal endurance by up to 23 per cent when compared to maltodextrin and sugars. In other research, a different patented HBCD made from potato, rice, and corn was found to be quickly absorbed into the blood stream 18.2 per cent faster than dextrose.
As carbohydrate science continues to develop, there will continually be better advancements in developing the most optimal carbohydrate that delivers performance benefits. If you are looking to help boost your endurance during your workout, and help kick start recovery post-workout, using an HBCD is definitely the way to go! Supplementing with any HBCD as part of your carbohydrate intake for the day will enhance nutrient absorption and help optimize glycogen re-loading while also improving muscle nutrient delivery and the muscle-building process!