Why Proper Hydration Is Critical with Gels
When you exercise, your body diverts blood flow from your digestive system to your working muscles. This redirection means your stomach has to work harder to process food and concentrated sugars, like those found in many energy gels. If a concentrated gel is not diluted with enough water, it can sit heavily in your stomach, drawing fluids from your body to aid digestion. This process, known as osmosis, can slow absorption, delay the energy boost, and potentially cause bloating, cramping, or nausea. By consuming the right amount of water with a gel, you help your body absorb the carbohydrates efficiently, providing a steady energy supply without digestive distress.
Classic Gels vs. Isotonic Gels: The Key Difference
Not all gels are created equal, and the type you use directly impacts your hydration strategy. Understanding the distinction is the first step to successful fueling.
Classic (Hypertonic) Gels
Classic energy gels are thick, high in concentrated carbohydrates, and low in water content. Because they are hypertonic (more concentrated than your body's fluids), they require external water to be diluted for proper absorption. Failing to take water with a classic gel is a common mistake that can lead to significant stomach issues during a long race.
Isotonic Gels
Isotonic gels are formulated with a pre-mixed balance of carbohydrates, electrolytes, and water. This means they have a similar concentration to your body's fluids, making them easier and faster to absorb without immediate extra water. This convenience makes them popular for runners who prefer not to carry water bottles or rely on aid stations, though overall hydration is still essential.
How Much Water Should You Drink with a Gel?
For Classic Energy Gels
The general recommendation is to consume approximately 200-250 ml (about 7-8 ounces) of plain water with each classic energy gel. This volume is crucial for diluting the gel's concentrated sugar, allowing for quick digestion and absorption. You don't have to drink it all at once; a few sips immediately after the gel and continued sips over the next 15-20 minutes can suffice. A good rule of thumb is to finish the recommended water intake before your next gel. Combining classic gels with a sports drink is not recommended, as it can overload your system with sugar and cause distress.
For Isotonic Energy Gels
As these gels already contain the required water for assimilation, you don't need to drink additional fluids immediately with them. Their thinner consistency aids digestion. However, this does not mean you can neglect your overall hydration. Isotonic gels provide energy but don't fully replace the fluids lost through sweat. You should still follow a regular hydration schedule by sipping water or an electrolyte drink between gels, especially in hot conditions.
Classic vs. Isotonic Gels: A Comparison
| Feature | Classic (Hypertonic) Gels | Isotonic Gels |
|---|---|---|
| Water Requirement | Essential for digestion (approx. 200-250ml per gel) | Not required immediately with intake |
| Carbohydrate Density | High (more energy per serving) | Lower (due to added water) |
| Absorption Speed | Slower if not taken with water | Faster and easier on the stomach |
| Convenience | Less convenient if not carrying water | More convenient on-the-go |
| Primary Use Case | When maximum energy is the priority | When GI comfort and convenience are priorities |
| Consistency | Thick and viscous | Thinner, more fluid |
Common Hydration Mistakes to Avoid
- Taking gels with sports drinks: This overloads your system with sugar, which can lead to stomach upset and slower absorption. Stick to plain water with classic gels.
- Neglecting pre-hydration: Ensure you are well-hydrated in the hours leading up to your activity. Starting dehydrated exacerbates the fluid-drawing effect of concentrated gels.
- Waiting until you're thirsty: Thirst is a sign that you're already dehydrated. Proactive and consistent hydration, combined with your gel intake, is key.
- Skipping water with classic gels: This is a recipe for disaster. The concentrated sugar can cause severe cramping and digestive issues, undermining your performance.
Training Your Gut and Perfecting Your Strategy
Just like training your muscles, you need to train your digestive system to handle fuel and hydration during exercise. Here are some practical tips:
- Practice in training: Never try a new gel or hydration strategy on race day. Use your long training sessions to test different gel and water combinations to see what your body tolerates best.
- Take smaller, more frequent doses: If you experience stomach issues, try taking smaller amounts of gel more often, with small sips of water. For example, consume a quarter of a classic gel with 50-60 ml of water every 15 minutes instead of a full gel every 45-60 minutes.
- Consider gel variety: Some brands and flavors may sit better with you than others. Experiment to find a gel and flavor you can tolerate, even late in a long event.
Putting It All Together: Your Race-Day Hydration Plan
For endurance events longer than 60-90 minutes, a structured fueling and hydration plan is your best asset.
- Start your day hydrated: Drink water or an electrolyte mix in the hours before the race. Ensure you have urinated sufficiently before the start.
- Take your first gel early: Consume your first gel about 45-60 minutes into your race, before you feel depleted.
- Regular intervals: Take subsequent gels every 30-45 minutes, depending on your needs and tolerance.
- Pair gels with water: If using classic gels, take 200-250ml of plain water with each one. If using isotonic gels, you can take it without extra water but continue to sip water or an electrolyte drink throughout the event.
- Listen to your body: Adjust your intake based on conditions and how you feel. Hotter weather requires more fluid intake. If you feel any stomach discomfort, ease off the gels and increase plain water intake for a bit.
For a deeper dive into the science behind how energy gels work and timing strategies, consider reading this guide on Runners Connect: Energy Gels for Running: How They Work and When You Should Use Them.
Conclusion
Optimizing your hydration alongside your energy gel intake is crucial for preventing performance-stalling stomach issues and maximizing energy absorption during endurance exercise. The key lies in understanding the difference between classic and isotonic gels. For classic, high-carbohydrate gels, adequate water intake (roughly 200-250 ml) is non-negotiable for proper digestion. Isotonic gels offer a convenient, water-free option for quicker absorption. By practicing your fueling strategy in training and listening to your body, you can confidently integrate gels into your routine for sustained energy and peak performance.
