Why is TORQ's carbohydrate matrix (2:1 glucose:fructose) more effective than using just one carbohydrate source (usually glucose or maltodextrin)?

Carbohydrates are an important source of energy during intense training and are essential during endurance training and competition. The more carbohydrates are oxidized (burned), the more impact it has on performance. The body has a limited endogenous supply of carbohydrates in the form of muscle and liver glycogen. That's an average of 500 g of carbohydrates. The carbohydrate reserve mentioned above can be depleted within an hour of very intense exercise. This, combined with a limited capacity for consuming carbohydrates, means that during intense activity you can run out of glycogen stores, contributing to a decline in performance and endurance.

Full glycogen stores will by no means last long. Especially with activities lasting several hours, there will sooner or later be a relief. Therefore, carbohydrate input during activity is imperative to slow glycogen depletion as much as possible. The more carbohydrates the body can absorb and oxidize, the lower the depletion of the body's glycogen stores. This results in maintaining performance and durability.

For several years it was believed that the maximum rate of oxidation of exogenous carbohydrates was about 1 gram of carbohydrate per minute (60 grams of carbohydrate per hour) when using a single form of carbohydrate such as maltodextrin or glucose. Higher oxidation was limited by the rate at which the body could absorb each form of carbohydrate. The intestinal transporter SGLT1, which absorbs carbohydrates from the intestines and carries them into the bloodstream, becomes saturated, which can lead to stomach and digestive disorders. Recent research suggests that a higher rate of carbohydrate oxidation is possible when mixing different carbohydrate derivatives such as glucose or maltodextrin and fructose.


Studies showing the benefits of a 2:1 matrix

A study by Wallis et. but in 2005 it established new guidelines for energy supply during endurance training. Wallis and his team showed that by combining maltodextrin (glucose) and fructose in a 2:1 ratio, the rate of carbohydrate oxidation increased by 40% and allowed up to 90 grams of carbohydrates to be consumed per hour. This is due to fructose supplementation, which uses intestinal transporters (GLUT5) other than glucose. The latter means that both carbohydrate derivatives can be absorbed independently, allowing for faster absorption and a higher rate of carbohydrate oxidation.

Currell and Jeukendrup (2008) investigated the direct effect of a 2:1 glucose-fructose hydration drink and its effect on performance. In a simulated 1-hour lab time trial, after 120 minutes of cycling, participants consumed either a placebo (flavored water), glucose, or a glucose-fructose drink at 55% of their VO2max. The results of the study were amazing. Performance improved by 8% when using a 2:1 glucose-fructose shake.

Triplet et al. 2010 also showed an 8.1% increase in performance due to the higher power output when using a glucose-fructose drink during a simulated 100km bike time trial. Triplett also noted that the participants reported no stomach or digestive upset. The same were the results of Rowlands and the Rowlands et al. (2012)) who investigated the use of maltodextrin and fructose during a 2.5-hour high-intensity bench drive and a mountain bike race.

A study by Jeukendrup and Moseley (2008) examined the effect of adding fructose to glucose on gastric emptying rate during a 120-minute cycling exercise at 61% VO2max. The results of the study showed that the administration of glucose and fructose increased gastric emptying rate and fluid intake compared to glucose alone.

Jeukendrup (2010) showed that carbohydrate oxidation is not related to body weight, so an intake of 90 grams of carbohydrates per hour can be achieved regardless of body weight. The intake of carbohydrates mentioned must be achieved gradually with intestinal training. It is necessary to start with a moderate intake of carbohydrates, which is then gradually increased.

Effect on post-workout recovery

After training, it is necessary to replenish the glycogen stores as quickly as possible, as this contributes to faster regeneration. Fast recovery is especially important for all athletes who do repetitive training, competitions or races. One of the most important limiting factors in replenishing these carbohydrate stores is the rate of carbohydrate absorption (Jentjens and Jeukendrup, 2003), which is significantly increased with the use of maltodextrin and fructose.

Recent studies (Wallis et al. 2008) examined the effect of a combined intake of glucose and fructose on the short-term recovery of muscle glycogen after exercise. The result of the study showed that both glucose and a mixture of glucose and fructose induced similar levels of glycogen resynthesis (restoration).

Research by Decombaz (Decombaz et al. (2011)) examined the effect of malodextrin and fructose on glycogen synthesis in the liver. The results showed increased storage of carbohydrates in the liver due to the addition of fructose. This is particularly important from a recovery standpoint, as reducing the time it takes to replenish glycogen stores can significantly improve subsequent performance. The less time it takes to recover, the sooner we can engage in high-intensity activities. The latter is especially important in stage races and back-to-back races.

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