Half Marathon Fueling Plan: How Many Gels Do You Really Need?
Half Marathon Fueling Plan: How Many Gels Do You Really Need?
Ask 10 runners how many gels you need in a half marathon, and you’ll get 10 answers. Here's how to calculate your fueling needs and choose the right products for your stomach, pace, and goals.
The Science of Fueling
Understanding your carbohydrate needs during a half marathon is crucial. Most half marathon runners require between 30 to 60 grams of carbohydrates per hour, depending on factors like race pace, duration, and body size. For example, a 2-hour runner might need approximately 60–90 grams in total.
Gel Math Explained
Most energy gels contain between 20 to 30 grams of carbohydrates. This means:
- 30g/hr: 1 gel per hour, totaling 2 gels for a 2-hour half marathon.
- 60g/hr: 2 gels per hour, totaling 4 gels for the same duration.
When to Start Using Energy Gels
Not every race requires in-race fueling. Your glycogen stores can power short, high-intensity events without additional carbohydrates. Use this quick reference to know when a fueling plan becomes important:
| Race Duration | Example Events | Fueling Recommendation |
|---|---|---|
| < 45 min | 5K, mile, track events | No gels needed — rely on pre-race meal and caffeine if desired. |
| 45–60 min | 10K, tempo efforts | Optional: 1 gel 15–20 min before race start if glycogen is low. |
| > 60 min | Half marathon, marathon, long triathlon, ultra | Yes — plan your gel schedule (1 every 30–45 min). Jump to Gel Calculator ↓ |
Tip: Start your first gel about 20 minutes into the race — not at the start line — and continue at regular intervals based on your target carb intake.
Race Day Gel Calculator
Pick your gel and race time. We’ll estimate how many you’ll need based on your target carb intake per hour (most runners land between 30–60 g/h). Practice this plan in training.
Total gels needed
Total carbs delivered
Interval between gels
Suggested gel schedule
This is a starting point. Practice during training to dial in timing and tolerance. Pair gels with small sips of water/electrolyte.
Products in Practice
Here's a breakdown of the various gel options and their benefits:
| Product | Carbs/Serving | Caffeine | Best For |
|---|---|---|---|
| Maurten Gel 100 | 25g | None | Easy digestion |
| Maurten Gel 100 CAF | 25g | 100mg | Caffeine boost |
| GU Original | 20g | 20mg | Affordable energy |
| GU Roctane | 20g | 35mg | Added sodium |
| NeverSecond C30 | 30g | None | Smooth absorption |
| NeverSecond C30 CAF | 30g | 75mg | Performance boost |
| UnTapped Energy Gel | 26g | None | Natural option |
| Extreme Sport Beans | 24g | 50mg | Chewable energy |
Sample Fueling Plans
- 90-min finisher (~30g/hr): 2–3 gels total.
- 2-hour finisher (~45g/hr): 3–4 gels total.
- 2.5-hour finisher (~60g/hr): 4–5 gels total.
For example, integrating one Maurten 320 bottle (80g) can replace three gels.
Mistakes to Avoid
- Forgetting electrolytes: Essential for maintaining balance.
- Taking all gels at once: Spread them out for sustained energy.
- Ignoring caffeine timing: Use strategically for a boost.
- Not practicing fueling in training: Avoid surprises on race day.
Conclusion
Fueling is a personal journey, and practice makes perfect. Utilize our tools to refine your strategy and ensure your half marathon is successful and enjoyable.
Shop Half Marathon Fueling Essentials
Explore our curated selection of energy gels, drink mixes, and more to fuel your run.
