Get Your Personalized Supplement StackSupplement Stack Quiz

Glycerpump

Also known as: Glycerol, Glycerin

Overview

Glycerol, also known as glycerin, is a naturally occurring compound found in foods and produced during fat metabolism. It is commonly used as a humectant and in pharmaceutical applications. In the context of sports supplements, glycerol is primarily used for its hyperhydration properties, which can enhance endurance performance and fluid retention. Glycerol acts as an osmotic agent, helping to retain water in the body. It is often combined with other ingredients in pump-enhancing supplements. Research on glycerol is of moderate maturity, with several meta-analyses examining its effects on hydration and performance. The available evidence is generally of moderate quality, with some studies having small sample sizes or methodological limitations. Glycerol is absorbed from the gastrointestinal tract and distributed throughout the body, primarily affecting the circulatory system by increasing plasma volume.

Benefits

Glycerol-induced hyperhydration (GIH) significantly enhances fluid retention compared to water-induced hyperhydration (WIH), with an increase of approximately 7.7 mL/kg body weight. Meta-analyses suggest that GIH can improve endurance performance by around 2.62%. Athletes may benefit from this enhanced endurance. While GIH may have limited effects on plasma volume expansion compared to other agents, its primary benefit lies in its osmotic action, promoting water retention. The effect size for fluid retention is significant, but the impact on endurance performance requires further investigation due to limited data. Benefits are typically observed within a few hours after administration.

How it works

Glycerol functions primarily as an osmotic agent, increasing the concentration of solutes in the body's fluids. This osmotic effect promotes water retention, drawing water into the blood and tissues. By increasing plasma volume, glycerol can enhance circulation and potentially improve endurance performance. The primary biological pathway involves the circulatory system, where glycerol's osmotic action helps maintain fluid balance. Glycerol is absorbed from the gastrointestinal tract and distributed throughout the body, influencing fluid dynamics without directly targeting specific molecular receptors.

Side effects

Glycerol is generally considered safe when used appropriately, but it can cause side effects in some individuals. Common side effects (occurring in more than 5% of users) include gastrointestinal discomfort, such as nausea or diarrhea. Less common side effects (1-5%) may include headaches and dizziness. Rare side effects (less than 1%) can include allergic reactions. Glycerol may interact with diuretics or other medications affecting fluid balance, potentially altering their effects. Individuals with severe kidney or liver dysfunction should avoid glycerol. Pregnant or breastfeeding women should consult healthcare providers before use. It's important to monitor for gastrointestinal side effects and ensure adequate hydration when using glycerol.

Dosage

The minimum effective dose of glycerol is typically around 1 g/kg body weight, with optimal dosage ranges around 1.1 ± 0.2 g/kg body weight. The maximum safe dose is not well established and should be guided by individual tolerance and medical advice. It is recommended to administer glycerol 1-2 hours before exercise. Glycerol is often used in liquid or gel forms for better absorption. Absorption can be influenced by gastrointestinal health. There are no specifically identified required cofactors. Users should start with a lower dose to assess tolerance and avoid exceeding recommended dosages to minimize potential side effects.

FAQs

When is the best time to take glycerol?

Glycerol is best taken 1-2 hours before exercise to allow for optimal absorption and fluid retention. This timing helps maximize its benefits during physical activity.

Is glycerol safe to use?

Glycerol is generally safe for most people when used as directed. However, it can cause gastrointestinal discomfort in some individuals, and those with kidney or liver issues should avoid it.

What are the expected benefits of taking glycerol?

The primary benefits of glycerol include enhanced fluid retention and potential improvements in endurance performance due to increased hydration. It is not a performance-enhancing drug but aids hydration.

How should glycerol be administered?

Glycerol is often used in liquid or gel forms for better absorption. Ensure adequate hydration when using glycerol and monitor for any gastrointestinal side effects.

Research Sources

https://fis.dshs-koeln.de/en/publications/meta-analysis-effects-of-glycerol-administration-on-plasma-volume – This meta-analysis examined the effects of glycerol administration on plasma volume. The study found that glycerol increases plasma volume more than fluid alone but has limited effects on doping-relevant parameters. The quality of the evidence was moderate due to variability in study designs.
https://journals.humankinetics.com/abstract/journals/ijsnem/17/4/article-p391.xml – This meta-analysis investigated the impact of glycerol-induced hyperhydration on fluid retention and endurance performance. The study concluded that glycerol significantly enhances fluid retention and improves endurance performance compared to water. However, the data on endurance performance was limited, and the study quality was moderate due to heterogeneity in study protocols.
https://pubmed.ncbi.nlm.nih.gov/28514721/ – This study investigates the effects of glycerol supplementation on muscle hydration and anaerobic power. The research suggests that glycerol can enhance muscle hydration, potentially leading to improved anaerobic power output during exercise. The findings contribute to understanding glycerol's role in optimizing physical performance through hydration strategies.
https://pubmed.ncbi.nlm.nih.gov/24996616/ – This research explores the impact of glycerol ingestion on thermoregulation and cardiovascular function during exercise in the heat. The study indicates that glycerol can aid in maintaining core body temperature and cardiovascular stability under heat stress. These findings highlight glycerol's potential benefits for athletes and individuals engaged in physical activity in hot environments.
https://www.researchgate.net/publication/5882675_A_Meta-Analysis_of_the_Effects_of_Glycerol-Induced_Hyperhydration_on_Fluid_Retention_and_Endurance_Performance – This meta-analysis focuses on the effects of glycerol-induced hyperhydration on fluid retention and endurance performance. The study demonstrates that glycerol significantly enhances fluid retention and improves endurance performance compared to water alone. These results support the use of glycerol as an effective hydration strategy for athletes and individuals seeking to improve their physical performance.