A big revolution in the supplement industry over the last year or so has been the use of intra-workout carbs. In my opinion this became a pretty big fad since the turn of 2010 until now. Discussions on online forums and experiments in the gym using different sources of carbs on what may give an athlete the extra advantage during their workout. The key factor to consider for intra-workout carbs would be up to the individual. Should I invest in them and what merit may they have? Most gym trainees who train say 60-90 minutes a day could they find a benefit from this in an intra-workout or pre-workout beverage? Can they hurt, or can they only be hurting our wallet? In this article I will break down each ingredient that I have researched over the last 4-5 years that have become popular.
The Anabolic Window Has Closed
Most people when it comes down to quick acting carbs think of the post workout window. In one of my previous articles I shot that down after Brad (Schoenfeld) and Alan (Aragon) did an amazing presentation on the topic. They had shown that meals spaced 4-6 hours apart were pretty optimal, and that if you ingested protein 1-2 hours pre-workout that the need for fast acting carbs immediately post-workout is not necessary. The same could be said with post-workout carbs as well.
Lets look at some science first and foremost regarding intra-workout carbs and see what has had to be said. A study from the Chinese University of Hong Kong, which showed a solution of around 40g of carbs and 20g of whey protein, did not show any added benefit over a prolonged study for those who trained for 60 minutes (this was done in 2013). This was not done on individuals weight training but based off those cycling. Some forms of cycling can be more detrimental to the human body than a weight training session as far as physical demand. We could also say the same for someone playing American football, soccer, and other sporting events. The need for those post-workout carbs for most of us are almost non-existent based upon this and many other studies. Based upon many studies it is shown that those who have had a meal prior to training will have a food overlap into the post-workout period.
A further study showing this was done by Koopmen when they combined a post-workout whey protein and carbohydrate drink. They used individuals in a group controlled study which showed there was no additional post workout exercise muscle protein synthesis with ample protein and carbs given a fed state. Again fed meaning they had some sort of a protein feeding 1-2 hours prior to training, which again references Alan and Brad’s recent work. The three groups from the study trained for 60 minutes and there was a protein alone group (post-workout), protein + carbs, and carb only post workout beverage consumed. In the end there were no real benefits when compared between all 3 groups.
The Need For Intra-Workout Carbs
Well first of all we need to understand that for optimal performance we need to prime our bodies for a workout. Meaning a good meal 60-90 minutes prior would not hurt and consuming the bulk of our carbs around our workout to maximize performance. For some of us that is not always the case. I like to train upon waking at 5 AM, and I train in a fasted state, because I found it optimal for me with better results. I wake up and take 10g of BCAA’s and then hit the weights. Over the years I have always negated intra-workout carbs. However, after doing some experimenting by using inta-workout carbs I have found; my recovery increased, my DOMS have been reduced, and I have also found myself pushing to new limits week in and week out. The key factor here may be controlling our insulin levels with a steady state of carbohydrates when we are depleting carbs and muscle is breaking down during exercise.
Lets use this analogy of a car and putting gas in the tank. If you were to go on a long drive (refer to this drive as a workout) would you want to go into that drive with an empty tank, a half empty tank, or a full tank. A full tank is the obvious choice. A full tank allows the body to run optimally. A half full tank means resorting to somewhat having your nutrition or calories in check for a workout. Then, there is running on empty and we all know how that feels. For those who may train fasted this may be the best bang for your buck (intra-workout carbs) to help you sustain energy, fuel, and provide optimal performance. It may also be of great benefit to those who may be doing two a day sessions, training the same bodypart two times a day, or those doing a very long session (2+ hours) and adding cardio on top of it to boot. Research has been done to show that CHO (Carbohydrate) ingestion during prolonged exercise may delay fatigue by over 40-50 minutes.
The Common Types Of Intra-Workout Carbs
Dextrose, Maltodextrin, HBCD (High Branch Cyclic Dextrins) and also Waxy Maize are probably 4 of the most popular choices.
Dextrose and Maltodextrin
Dextrose/Maltodextrin are forms of a simple sugar that your body produces naturally. It is also found in our blood and various cellular processes, such as respiration and glycolysis. You can also find dextrose being used in medical applications when people cannot consume enough liquids or help to inject medicine. Dextrose & Malto are simple sugars and something already naturally occurring in the body. This passes through the small intestine at very alarming rates and the speed of absorption may make this a good carbohydrate to utilize during the intra-workout period.
Using dextrose during your workout allows your body to sustain or replace the glucose that’s depleted during intense training. It is important to know that there is an upper limit to intra-workout carb intake. Aiming to use too many carbs is just going to be stored or raise insulin to very high levels (which is never good in any case for bodybuilding). Osmolality is the measure of the concentrate (Dextrose) through our system to being dissolved and being processed to help us sustain energy levels throughout our workout.
Another popular ingredient was Waxy Maize, which acts kind of like Dextrose, because it empties into the stomach at a very rapid pace. During this process the glucose is hydrolyzed into free glucose through the digestive tract of the small intestine before they are absorbed into the blood stream. The fast pace of the high molecular glucose provide a sustained (key word sustained) energy release into the bloodstream it helps keep insulin levels stable during training. This allows these carbs to help aid in optimal performance.
These carbs are almost identical to amylopectin (a glucose polymer of a high branched structure) the long chain of glucose aids in extensive branching to a low osmolality solution. Due to how fast this processes through the stomach faster than a glucose solution (such as dextrose and malto dextrin) these provide a steadier, streaming, and slower release of glucose into the blood stream. This prevents insulin from peaking to crazy high levels and aids a smoother energy hit. +1 for Waxy maize over Dextrose or MaltoDextrin.
Highly Branched Cyclic Dextrin
While this passes at a similar speed, if not faster, than Waxy Maize but maintains a better release of glucose in the body. Highly Branched Cyclic Dextrin is formed by the breakdown of amylopectin using enzymatic treatments that formed into clusters. These clusters are then formed in to larger chains using additional branching enzymes. The weight of the object is around 150,000-160,000 Da, so they have a very low osmolality (lower than Dextrose, Waxy , and also MaltoDextrin) with the fastest gastric emptying time. Dextrose and malto Dextrin may be around 180,000 Da with Waxy Maize around 170,000 Da.
The key thing with HBCD is there is more research to back these carbohydrates not only in human studies, but also in rodent and animal studies for athletic performance. These have been studied on mice, humans, and also rats which showed a drastic increase in athletic performance. The release and steady supply of carbohydrates that maintained in the blood stream showed these carbohydrates to be the top tier choice among the others.
The amount of dextrose, maltodextrin, and waxy maize being used lately has been minimal compared to the ever so popular HBCD rave. What will the industry show in the next few years? We have no idea, but the research is clear HBCD is by far the winner.