Nutritional Supplements Library
What is Glycerol?
Glycerol is a 3-carbon molecule that is backbone of triglycerides and phospholipids which is produced naturally in the body as a result of normal metabolism. Glycerol alcohol is a colorless, odorless, hygroscopic, and sweet-tasting viscous liquid. Glycerol is a sugar alcohol and has three hydrophilic alcoholic hydroxyl groups (-OH) that are responsible for its solubility in water. It is 60% as sweet as sucrose and has a caloric value of 4.32 per gram. Glycerol is technically a sugar alcohol. The FDA (food and drug administration) had no choice but to list it as a carbohydrate only because there was nothing else to list it under.Glycerol can be obtained during the fermentation of sugars if sodium bisulfate is added with the yeast. It has an osmotic action, is well tolerated, is rapidly absorbed by the gastrointestinal tract and is safe at a specified quantity. It is, as a result of its high osmolality, a hydrophilic product, which means that water, is greatly 'attracted' by this particular substance. Instead of being rapidly excreted by the human body, an excessive ingestion of water or sports drinks accompanied by glycerol will be retained by the body longer. Glycerol acts like a sponge, forcing water to stick with it.
What is the effective dosage for glycerol supplementation?
If you do decide to try glycerol, you might like to use the protocol that produced significant hyper-hydration in one of the studies mentioned above(5). Bear in mind, though, that it involves drinking nearly two liters of fluid, which will lead to a weight increase of 3% for a 70kg athlete and 4% for one weighing 50kg! If you're a runner, you may find that this extra mass outweighs, quite literally, any potential performance benefits!
Montner's glycerol ingestion protocol, beginning 150 minutes (2.5 hours) before exercise:
• 0 minutes - drink 5ml per kg of your body weight of a 20% glycerol solution (1 part glycerol to 4 parts water);
• 30 minutes - drink 5ml/kg of water;
• 45 minutes - drink 5ml/kg of water;
• 60 minutes - drink 1ml/kg of a 20% glycerol solution and 5 ml/kg of water;
• 90 minutes - drink 5ml/kg of water;
• 150 minutes - begin exercise.
What are the benefits of glycerol supplementation?
• Glycerol has a dehydrating effect. This is based on the fact that glycerol has an ability to hold onto water, Endurance athletes can utilize glycerol in conjunction with extra water prior to an event in order to support hydration and therefore enhance performance in long distance running.
• It increases blood volume, enhances temperature regulation and improves exercise performance in the heat.
• Where substantial dehydration is likely to be a problem ie long, strenuous event in hot and humid conditions, Glycerol would be athletes best choice.
What are the side effects of glycerol supplementation?
Glycerol ingestion is associated with such side effects as stomach upsets headaches, hyper tension and blurred vision at higher doses. If you are tempted to try glycerol, make sure you've tried proper hydration strategies using good old water or fluid replacement drinks
• it should not be used by people with hypetension, children and pregnant unless a doctor's guidance.