How to Fuel for Long Runs (Without Gut Issues)

When your run stretches past 90 minutes, fuelling shifts from optional to essential. But for many women, the longer the run, the more likely gut distress enters the picture. Bloating. Cramps. Nausea. Or the dreaded mid-run toilet dash.

This guide is for the woman who wants to run long and feel strong, without sacrificing her gut.

Why Gut Issues Happen (Especially for Women)

Gut discomfort during long runs is common, but not inevitable. Women may be more prone due to:

• Hormonal fluctuations that slow digestion.
• Higher rates of IBS, bloating, and anxiety that heighten gut sensitivity.
• Tighter GI windows pre-menstrually, where gastric emptying is slower.
• Reduced blood flow to the gut during hard efforts, making digestion harder.
• Fuelling with high-sugar products or ingredients your system isn’t used to.

Add in bounce, jostling, and gels with questionable ingredients, and it’s a recipe for disruption.

Train Your Gut Like You Train Your Legs

Gut issues aren’t a sign of weakness: they’re a sign of under-preparation. Just as your muscles adapt to load, your digestive system adapts to fuelling if you train it.

• Start small: Introduce fuelling on shorter runs, half a gel or a small sip of carb drink every 20–30 minutes.
• Progressive loading: Gradually increase carb intake toward your race target (40–60g per hour is common).
• Mix sources: Use a variety of carbs (glucose + fructose) from gels, chews, and real food so your gut learns flexibility.
• Practice timing: Don’t wait until you feel depleted. Train your body to expect fuel every 25–35 minutes.
• Simulate race day: Practise with the effort, heat, and products you’ll actually use in competition.

Adaptation takes weeks: but it works. Research shows the gut can increase its absorption capacity with consistent training.

Principles of Gut-Friendly Fuelling

1. Start with a calm baseline
   Avoid triggering foods 24 hours before a long run. For many women this means limiting:
• Cruciferous veg (broccoli, kale).
• Artificial sweeteners.
• Dairy (unless well tolerated).
• High-fat, fried foods.
2. Eat early, not late
   Give yourself 90–120 minutes after a full meal before running. Easy options include:
• Low-FODMAP toast with nut butter.
• Oats with banana and cinnamon.
• Plain rice with scrambled tofu or egg.
3. Fuel before you feel flat
   Start 30–45 minutes in, then top up every 25–35 minutes. Small amounts frequently reduce gut load and prevent crashes.

What to Eat: Options That Go the Distance

Whole-food based

• Boiled potato halves with salt.
• Medjool dates with nut butter.
• Homemade rice cakes with maple syrup.
• Banana oat cookies.

Commercial products (gut-friendly)

• Skratch Labs Energy Chews & Hydration Mix.
• Spring Energy gels (real food base).
• Tailwind Endurance Fuel (mixes easily with water).
• UnTapped Maple Syrup Packs (single ingredient).

All of these are available via Aid Station: a trusted Her Trails partner where you can stock up, trial different options, and find what works for your system before race day.

Plant-based or gut-sensitive runners

• Use low-FODMAP staples like rice, peanut butter, maple syrup.
• Swap to gluten-free oats or bread if needed.
• Avoid sorbitol, xylitol, and other sugar alcohols in “sugar-free” products.

Hydration Matters More Than You Think

Dehydration makes gut issues worse. Sip small amounts every 15–20 minutes, especially if you are:

• Running in heat.
• Menstruating or ovulating (fluid needs increase).
• Breathing heavily through your mouth (dry mouth = gut strain).

Electrolytes help fluids absorb more efficiently. Products like Skratch or Tailwind (both via Aid Station) support this balance.

Listen to Your Body, Not the Marketing

You don’t need three gels an hour to perform. Some women thrive on alternating chews, water, and flat Coke. Others prefer a steady mix of real food and one gel per hour.

There is no one-size-fits-all. Track what feels good in training. Notice what doesn’t. Get curious. The only mistake is waiting until race day to experiment.

Reflection Prompt

• What does “strong” fuelling look and feel like in my body?
• Where might I be fuelling from fear or pressure, instead of self-trust?