Run Republic
  • Race Calendar
  • Latest
  • Performance
  • Interviews
  • Club News
  • GB
  • Contact Us
  • Performance
  • Beginner's Corner
  • Nutrition & Recovery
  • Gear & Tech
  • Injury Prevention
  • Plans and Programmes
NI Running Show

Nut Bars & Carb Gels: What is the Safest Marathon Fuel for Your Stomach?

Nut Bars & Carb Gels: What is the Safest Marathon Fuel for Your Stomach?

Published on: 30 Sept 2025

Author: Phil Knox

Categories: Nutrition & Recovery

Mid run fuelling is a delicate art. You need enough energy to keep moving, but not so much that your stomach stages a full blown protest halfway through a country road with no toilets and suspicious looking nettles.

And here’s the kicker, what works for one runner might leave another frantically scanning for bushes. It’s a gamble every time you try something new. But some bets are safer than others.

The Gel Question

Carb gels are designed for performance. They’re:

  • High in fast digesting sugars
  • Easy to carry
  • Quick to eat mid stride
  • Made to keep you going when your tank’s nearly empty

But they also have a reputation: sticky, sickly, and occasionally explosive, in both directions.

The trick? Practice. Never try a new gel for the first time on race day. Your stomach needs to get used to them. And always, always, take them with water. Gels on a dry throat are how regrets are made.

Nut Bars: Tasty, But Tricky

They’re great for hiking. Not so great for running at pace.

  • High in fat and fibre = slow to digest
  • Can feel heavy or greasy mid run
  • More likely to bounce around in your stomach like a rock in a tumble dryer

If you’re out for a gentle long run and stopping occasionally? A nut bar is grand. But if you’re pushing the pace or racing? It’s a risky choice. That “healthy snack” could turn into a gut wrenching nightmare by mile seven.

Safer Alternatives

  • Soft cereal bars (low fibre ones)
  • Energy chews or jelly sweets
  • Banana halves if you can carry them without turning them into mush
  • Mashed potato in a ziplock (yes, ultra runners do this, don’t knock it till you try it)

The goal is quick carbs that are easy on the gut, easy to chew, and won’t require a dental appointment after.

Warning Signs

If you start feeling:

  • Nausea
  • Cramps
  • A sudden urge to sprint off course with your hand on your waistband…

…it’s already too late. Back off the pace, sip water, and start planning your escape route.

Conclusion

Mid run fuelling doesn’t have to be a disaster. Stick to easy carbs, keep your fat/fibre intake low, and always test your choices on training runs first, ideally somewhere with toilet access. Gels might not taste amazing, but they’re designed to get the job done without turning your long run into a tactical survival mission.

 

Related Articles

  • Running on Empty: When Is Fasted Running Actually Worth It?

    23 Sept 2025

  • Salt, Sweat and Electrolytes: Do You Really Need Tablets?

    16 Sept 2025

  • Snacking on the Go During a Marathon: What Fits in a Pocket and Won’t Melt?

    09 Sept 2025

  • Is Chocolate Milk Still the King of Recovery?

    02 Sept 2025

Run Republic
  • Run Republic
  • Run Ulster
  • Run United States
Contact
More
  • Latest
  • Track & Field
  • Road Running
  • Marathons
  • Blogs
  • All Categories
About Us
  • Contact
  • About
Legal
  • Impressum
  • Privacy Policy
  • Cookie Settings
Follow Us
  • Facebook
  • Twitter
  • Instagram

© 2025 Run Republic. All Rights Reserved.