The Core Principle: Isotonic vs. Hypertonic
To understand the distinct mechanism of action for SiS gels, it's crucial to grasp the concept of 'tonicity.' Tonicity refers to the concentration of dissolved particles, such as carbohydrates and electrolytes, in a fluid. In the world of sports gels, this concentration dictates how the gel is absorbed by the body.
- Isotonic Solution: An isotonic fluid has a similar concentration of particles to the body's cells and blood plasma. SiS gels are formulated to be isotonic, which means they can pass from the stomach to the small intestine and be absorbed into the bloodstream without the body needing to draw extra water into the gut to dilute them. This prevents the gastric bloating and discomfort often associated with other gels and allows for faster energy absorption.
- Hypertonic Solution: Most conventional energy gels are hypertonic, meaning they have a higher concentration of particles than the body's fluids. To process a hypertonic gel, the body must first pull water from the bloodstream into the stomach to dilute it, a process that can cause feelings of bloating, stomach cramps, and delayed energy availability.
The Role of Maltodextrin
The primary carbohydrate source in SiS gels is maltodextrin, a complex carbohydrate derived from maize. This choice of carbohydrate is key to the gel's isotonic properties. Unlike simple sugars like glucose or fructose, maltodextrin is a polymer of multiple glucose units. SiS uses a specific type of corn-based maltodextrin with a precise molecular weight to achieve its signature low-osmolarity formula.
When consumed, the maltodextrin is broken down into glucose by enzymes in the digestive system. Because maltodextrin is a large molecule, a smaller number of molecules are needed to provide a significant amount of carbohydrate compared to simple sugars. This keeps the gel's overall particle concentration (osmolarity) low, maintaining its isotonic nature and allowing for rapid, fuss-free absorption. This quick absorption helps in the efficient replenishment of muscle glycogen stores, delaying fatigue during prolonged exercise.
Maximizing Energy Absorption and Minimizing Gastric Distress
The physiological benefits of the SiS isotonic formula are twofold: rapid absorption and reduced gastric discomfort. During high-intensity exercise, blood flow is diverted away from the digestive system to the working muscles. In this state, the digestive system is less efficient at processing food. A hypertonic gel exacerbates this issue, as the body struggles to both supply blood to the muscles and pull water into the gut for digestion.
SiS gels bypass this problem entirely. By being isotonic, they move quickly through the stomach without taxing the digestive system, delivering a fast and continuous supply of energy directly to the bloodstream and working muscles. This is particularly advantageous during long endurance events, where consistent, easy-to-digest fuel is critical for maintaining performance.
Key Stages of Action
- Ingestion: The gel is consumed, its watery texture making it easy to swallow without extra fluid.
- Stomach Emptying: The isotonic nature allows the gel to pass through the stomach and into the small intestine quickly, unlike hypertonic gels which can sit in the stomach and cause bloating.
- Absorption: The maltodextrin is rapidly absorbed in the small intestine, breaking down into glucose that is directed into the bloodstream.
- Energy Supply: The delivered glucose quickly replenishes depleted blood sugar levels and muscle glycogen stores, combating fatigue and supporting continued performance.
A Spectrum of SiS Gels for Varied Needs
Science in Sport has expanded its product line to include several variations, each with a specific purpose for different types of athletic demands.
- SiS GO Isotonic Energy Gel: The foundational product, providing a pure and rapid carbohydrate boost for all types of endurance training.
- SiS GO Energy + Electrolyte Gel: Combines the isotonic formula with essential electrolytes (sodium, potassium, magnesium) to aid hydration, especially important during hot weather or heavy sweating.
- SiS GO Energy + Caffeine Gel: Adds a performance-enhancing boost of caffeine to the isotonic formula, increasing alertness and concentration during longer, more demanding efforts.
- SiS Beta Fuel Gels: Optimized for the highest carbohydrate demands, featuring a 1:0.8 ratio of maltodextrin to fructose to increase carbohydrate oxidation efficiency, allowing for a higher intake per hour with less gastric stress.
Comparison: SIS Isotonic Gels vs. Traditional Hypertonic Gels
| Feature | SIS Isotonic Gels | Traditional Hypertonic Gels |
|---|---|---|
| Key Characteristic | Isotonic (similar concentration to body fluids) | Hypertonic (higher concentration) |
| Primary Carbohydrate | Maltodextrin (low GI in gel form) | Fructose, Glucose (simple sugars, high GI) |
| Fluid Requirement | No extra water needed for digestion | Requires water to aid dilution and absorption |
| Stomach Emptying | Rapid and efficient | Slower, as water is drawn from the body into the gut |
| Risk of Gastric Distress | Significantly lower risk of bloating or cramps | Higher risk, especially if not consumed with sufficient water |
| Energy Absorption | Fast and steady delivery of carbohydrates | Can be delayed if not properly diluted |
| Consistency | Watery and light | Thicker, more syrupy paste |
Conclusion
By leveraging the science of tonicity and utilizing a specific form of maltodextrin, SiS gels offer a highly efficient and stomach-friendly method of in-race fueling. The isotonic formula ensures rapid absorption of carbohydrates without causing the gastrointestinal issues often associated with thicker, hypertonic gels. For endurance athletes, this means a reliable and convenient source of energy that minimizes discomfort and supports sustained, peak performance, especially during long training sessions and races. The different variants, such as those with added electrolytes or caffeine, further allow athletes to tailor their nutrition strategy to their specific needs. Understanding how does SIS gel work enables athletes to make informed decisions about their fueling, a critical component of successful endurance sports. For more detailed information on SiS products, you can visit the Science in Sport official website.
