What to Eat Before a Half Marathon (and What to Avoid)

Your half marathon is right around the corner, and while logging miles and sharpening workouts gets you to the start line, nutrition is what carries you across the finish. Whether you’re chasing a PR or just finishing strong, dialing in your fueling strategy is one of the best ways to set yourself up for success.

In this guide, we’ll walk through pre-race fueling, during-the-race nutrition, product comparisons, and common mistakes to avoid — all tailored for half-marathon runners.

Table of Contents

1. Introduction to Race Day Nutrition
2. Essential Pre-Race Nutrition Tips
3. Pre-Race Fueling Strategy & Timing
4. During the Race Fueling Strategy
5. Compare Products
6. FAQ for Race Day Nutrition
7. Common Mistakes to Avoid

1. Introduction to Race Day Nutrition

Race day nutrition isn’t one-size-fits-all. Your body, preferences, and training all play a role in what works best. That said, there are core principles every runner can apply:

• Carbs = primary fuel source
• Hydration = ongoing strategy
• Caffeine = performance enhancer (if tolerated)
• Familiarity = no experimenting on race day

2. Essential Pre-Race Nutrition Tips

General rules of thumb before any race:

• Carbohydrate-focused: Choose oats, rice, toast, bagels, bananas, or other simple carbs that provide readily available energy.
• Limit fats & fiber: They slow digestion and can upset your stomach mid-race.
• Stick with what you know: Practice your race breakfast in training to avoid surprises.
• Hydrate early, not late: Get fluids in the morning, but avoid chugging water in the final hour before the start.

🧠 Pro Corner: The Science Behind Pre-Race Fueling

• Carbohydrates empty fastest. When you eat carbs, your stomach clears them into the small intestine relatively quickly, which means glucose hits your bloodstream sooner — crucial for topping up glycogen before the race.
• Fat and fiber slow gastric emptying. High-fat or high-fiber foods linger in the stomach, delaying carb absorption and increasing the risk of GI distress (cramping, bloating, urgent bathroom stops).
• Timing matters. Typical gastric emptying: simple carbs ~1–2 hrs; mixed meals (with fat/protein) ~3–4 hrs; high-fat/high-fiber ~4+ hrs. Aim for your main pre-race meal 3–4 hours before the gun.
• Hydration is balance. Slamming a big bottle of water in the last hour can dilute electrolytes and slow gastric emptying. Sip steadily earlier; keep it light in the final 60 minutes.

3. Pre-Race Fueling Strategy & Timing

The half marathon requires more preparation than a 5K — your fueling window matters.

4 hours out (main meal): ~2–3 g carbs per kg bodyweight.

• Example: bagel with jam, banana, oatmeal with honey, small sports drink.
• Product tie-in: top off with Maurten Drink Mix 320 (80 g carbs) or NeverSecond C90 High Carb Drink Mix (90 g carbs) for easy liquid carbs.

2 hours out (optional snack): ~30–60 g carbs.

• Example: granola bar or GU Waffle.

1 hour out (hydration check + caffeine if desired):

• Small sips of Nuun Sport Hydration.
• Caffeine option: Maurten Gel 100 CAF or NeverSecond C30 Caffeine Gel (~30 min before gun).

15–30 minutes out: Quick carb boost if needed.

• Best picks: Maurten Gel 100, NeverSecond C30 Energy Gel, GU Energy Gel, or Untapped Energy Gel.

4. During the Race Fueling Strategy

The half marathon is long enough to deplete glycogen stores but short enough that fueling can feel tricky. The key: steady carbohydrate intake, proper hydration, and electrolytes to support performance.

Carbohydrate Needs

• Target: 30–60 g of carbohydrate per hour.
• Why: Even if you start well-fueled, your body will tap into stored glycogen and need extra carbs to maintain pace.
• How to achieve: Most gels and chews provide 20–30 g per serving. Plan 2–3 servings per hour depending on your pace.

Example plan for a 2-hour half marathon:

• Gel at mile 3 (~20 min)
• Gel at mile 6 (~45 min)
• Gel at mile 9 (~70 min)
• Optional boost at mile 11–12 (~90 min)

Hydration Strategy

• Aim for 3–6 oz of fluid every 15–20 minutes (roughly a few sips at each aid station).
• Water alone may not be enough — especially in warm or humid conditions.
• Pair fluids with electrolytes to prevent cramping and support muscle function.

Top picks:

• Nuun Sport Hydration (electrolyte tablets with light carbs).
• SaltStick Fast Chews (quick, portable electrolyte option).

Caffeine Strategy

• Caffeine has been shown to improve alertness and endurance.
• Best used in the later stages of the race when fatigue sets in.
• Typical dose: 3–6 mg/kg of body weight across the race, but many athletes get a performance benefit with as little as 75–200 mg.

Options to consider:

• Maurten Gel 100 CAF — 100 mg caffeine.
• NeverSecond C30 Caffeine Gel — 75 mg caffeine.

Take one 30 minutes before the race (if tolerated) or save for miles 7–10 when fatigue builds.

Gel vs. Drink Mix Strategy

Both can work — the best choice depends on your stomach tolerance and access to aid stations.

• Gels + Water: Flexible, portable, easy to time with aid stations.
• Drink Mix (Maurten 320 or NeverSecond C90): Provides steady carb delivery (80–90 g per serving) but requires carrying your own bottles or using a belt/vest.

Pro tip: If you use a high-carb drink mix before or during the race, you may need fewer gels.

Solid Food Mid-Race

Some runners prefer something chewable or solid to break up gel intake.

• Untapped Waffle or GU Waffle can be good choices early in the race (first 30–40 min).
• Avoid solids in the final miles — stick with quick-digesting gels and drinks.

Example Race-Day Fueling Timeline (Half Marathon, ~2 Hours)

5. Compare Products

When it comes to fueling, you’ve got options. Here’s how the products we carry stack up:

6. FAQ for Race Day Nutrition

Q: Do I really need fuel for a half marathon?
A: Yes. Even well-trained runners benefit from 30–60g carbs/hour to avoid hitting the wall and to maintain pace. Gels like Maurten Gel 100 or GU Original Energy Gel make it easy to hit this target.

Q: What about caffeine?
A: It’s a proven performance aid — but only if you’ve practiced it in training. Most runners use 75–200mg across a race. Good options include Maurten Gel 100 CAF (100mg) or NeverSecond C30 Caffeine Gel (75mg).

Q: Should I bring my own gels or rely on aid stations?
A: Always bring what you’ve practiced with. Don’t risk a new brand on race day. Stock up on your favorites ahead of time, like NeverSecond C30 Gel or Untapped Energy Gel.

Q: How early should I start fueling during the race?
A: Start sooner than you think. Take your first gel or sip of carbs around 20 minutes in (mile 3–4). For example, try a Maurten Gel 100 at mile 3, then rotate with other options like GU Roctane Gel.

Q: What’s the difference between gels, chews, and drink mix?
A: They all deliver carbs, but absorption and convenience differ:
– Gels = fast and portable (NeverSecond C30).
– Chews = easy to spread out over miles (Extreme Sport Beans).
– Drink mixes = steady carb delivery (Maurten Drink Mix 320 or NeverSecond C90).

Q: How much should I drink during a half marathon?
A: Aim for 3–6 oz every 15–20 min, depending on heat and sweat rate. Don’t just drink water — pair with electrolytes like Nuun Sport Hydration or SaltStick Fast Chews.

Q: Can I “carb load” the night before?
A: Yes, but it doesn’t have to be a giant pasta dinner. Think steady carbs across the 1–2 days leading up to the race. Lighter options like GU Waffle or liquid carbs from Maurten Drink Mix 320 can top off glycogen without weighing you down.

Q: What if my stomach gets upset mid-race?
A: Switch to smaller sips or chews, avoid solids late in the race, and use electrolytes like SaltStick Fast Chews to help balance fluids. Always practice fueling in training to reduce surprises.

Q: Is it possible to over-fuel?
A: Yes. Taking in more than 90g carbs/hour can cause stomach distress unless you’ve trained your gut. If you’re experimenting with higher fueling, use steady sources like NeverSecond C90 Drink Mix rather than cramming in too many gels at once.

Q: Do I need electrolytes if it’s a cool day?
A: You may need fewer, but sodium losses still matter over 13.1 miles. Even in cool temps, aim for some sodium replacement every 45–60 minutes. Products like Nuun Sport or SaltStick Fast Chews provide an easy boost.

7. Common Mistakes to Avoid

• Over-hydrating in the last 60 minutes before the race.
• Trying new gels or supplements for the first time on race morning.
• Skipping pre-race breakfast entirely.
• Eating too much too close to the start.
• Forgetting electrolytes on warm/humid race days.

👉 Bottom line: train your gut like you train your legs. Practice your fueling strategy in the weeks before the Fort Ben Half, and show up with confidence on race day.