The Science

Science Fitness GlycoSource is the only commercially available endurance supplement whose formulation is clinically proven to aid glycogen synthesis in both the muscles and the liver. The clinical trials undertaken produced amazing results, and to date have been the only trials that have measured the repletion of glycogen in both the liver and the muscles.

The clinical trial program was designed to test the benefits of the GlycoSource formulation. The team of expert sports scientists at the world renowned Carnegie Faculty at Leeds Metropolitan University investigated the effects of a specific Carbohydrate (CHO) blend of Maltodextrin (MD) and Galactose (GAL), with and without protein (PRO) and supplementary amino acids (AA) on recovery from endurance exercise and subsequent fuel utilisation during endurance performance.

The team knew that liver and muscle glycogen were essential sources during prolonged moderate to high intensity exercise . They also knew that the value of glycogen reserves in liver and muscle is related to endurance performance , but the consumption of protein and amino acids have other potential benefits, such as post exercise muscle protein synthesis. This can positively affect gains in muscle protein and strength Therefore it stood to reason that the optimisation of short term replenishment of both liver and muscle glycogen stores through a nutritional supplement was going to be potentially important for performance.


The Trials

The clinical trial involved three separate sets of trials with a total of 24 participants. Each trial comprised multiple conditions to which all the participants were exposed. These conditions were that the participants were given 3 different types of formula in water to consume and ingest after exhausting exercise.

The results from taking the varying formulas in Trial 1 (T1) and Trial 2 (T2) were used to formulate the optimum energy recovery formulation comparisons for Trial 3 (T3) in which the MRS scans were conducted to measure the glycogen production across the conditions.

Trials T1 and T2 were also vital to understanding the maximum rate of Oxygen consumption for each participant. This measurement is known as the athletes VO2max. and trial T3 worked to very specific VO2max parameters for each athlete.

In trial T3, participants cycled for 45 minutes at 70% VO2max, before completing six 1 minute sprints at 120% VO2max separated by a 2 minute recovery at 50% VO2max. Subsequently, participants cycled for another 45 minutes at 70% VO2max.

The trial conditions ingested by the athletes were as follows:

Details, Note: n =no of participants, 13C refers to isotope labelled carbon.

T1 – Performance, Plasma Variables, n=9, three conditions

i) CHO(MD) ii) CHO(MD) + P/AA iii)CHO(MD +Gal) +P/AA

T2 – Performance, Plasma Variables, Fuel Utilisation (13C isotopes), n=8, three conditions<

i) CHO (MD +Gal) ii) CHO(MD + Gal) +P/AA iii) 0 Energy Placebo

T3 – MRI glycogen, n=7, two conditions

i) CHO(MD + Gal) + P/AA ii) CHO (MD+Gal)


The Analysis

After Trial 3, participants undertook a 4 hour recovery programme. Immediately after the exercise, they ingested quantities of either the MD & GAL beverage, or the MD & GAL & PRO + AA beverage, presented using a randomised double blind study design, where both the tester and the subject did not know the conditions the subject will be ingesting. They then consumed the beverage again every 30 minutes after, consuming a total of 2.7 litres in the 4 hour period.

Blood samples were taken throughout the recovery period, and measurements of Glycogen were taken in the muscle and the liver both immediately after the exercise and at the end of the 4hr recovery period using 13C magnetic resonance spectroscopy, a whole body MRI scan.


The Results

Due to the complexity of the trials, potential risk to the participant and expense of measuring glycogen in both muscle, and, especially, the liver, this is the first study ever to evaluate, using 13C magnetic resonance spectroscopy (MRS), the effects of MD and GAL, with and without PRO and AA after glycogen-depleting endurance exercise.

The trial results successfully displayed a huge increase in the glycogen levels of both the liver and the muscle compared to immediately after exercise, optimising the athlete’s recovery time.

One major discovery was the fact that the insulin response, which plays an important role in liver glycogen synthesis, doubled after the MD-GAL-PRO+AA formulation was ingested.

Another discovery was that despite the lower content of carbohydrate in the MD-GAL-PRO+AA formulation, there was no significant difference detected in the glycogen measured as a result of ingesting the two formulations. Therefore although the MD-GAL-PRO+AA formulation contained44% less carbohydrate than the alternative MD+ GAL formulation, the synergistic boost to glycogen recovery provided by MD-GAL-PRO+AA achieved equal levels of glycogen repletion.

This suggested that the increased insulin response compensated for the lower carbohydrate content in the MD-GAL-PRO+AA. For the endurance athlete this is a game changing discovery. Most formulations on the market rely on carbohydrates to provide the positive increases in muscle glycogen synthesis, yet it has been proven that there is a limit to the amount of assistance carbohydrate can provide, just ingesting more carbohydrate will not work.


The Reason to Choose GlycoSource

GlycoSource delivers extraordinary results using less carbs to do it. The lower the volume of carbohydrate ingested during exercise, the greater the benefit to the athlete and the inclusion of protein and amino acids in the formulation also provide a benefit to maintaining muscle function.

These amazing discoveries are formulated in GlycoSource, the next big revolution in endurance supplementation.


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