The Science of Slow-Burning Carbs for Athletes

If you’ve ever bonked halfway through a long run or ride, you know how brutal energy crashes can be. For endurance athletes, staying fueled isn’t just about eating—it’s about fueling smart. And that starts with the type of carbs you choose.

The solution? Slow burning carbs—a game-changing source of steady, sustained energy that helps you go the distance without crashing.

What Are Slow Burning Carbs?

Slow burning carbs—also called slow release carbs or low glycemic carbs—are digested gradually. Instead of flooding your system with a quick sugar hit, they provide a smooth, extended release of energy that keeps your body moving and your mind sharp.

• Slow burn = Consistent energy over 75+ minutes
• Fast burn = Spike, crash, repeat
  
  

Endurance athletes need fuel that lasts, not fuel that fades. That’s the slow carb advantage.

How Do They Work?

Unlike fast burning carbs like glucose or maltodextrin—which spike your blood sugar and drop you fast—slow carbs digest at a steady pace. They keep blood sugar stable, insulin levels low, and energy delivery even. For endurance athletes, this means fewer bonks, better pacing, and more efficient fat-burning during long efforts.

• Stable blood sugar
• Less reliance on frequent fueling
• Enhanced fat metabolism
• Reduced GI distress
  
  

Research shows that low glycemic carbohydrates improve performance in endurance activities lasting over 60 minutes. [Source]

Fast Burning vs. Slow Burning Carbs

The difference? One fuels a sprint. The other fuels your entire race.

Why Endurance Athletes Need Slow Release Carbs

Glycogen stores deplete fast during long runs, rides, or races. Replacing that energy with fast carbs might work short-term, but they can backfire: unstable energy, stomach issues, and dependency on constant fueling. Slow burning carbs keep you steady, focused, and strong—mile after mile.

• More stable pacing and performance
• Fewer energy crashes mid-race
• Less need for frequent refueling
• Gentler on the stomach
  
  

That’s why elite athletes—and smart amateurs—are rethinking their fueling strategies.

UCAN + LIVSTEADY™: Fuel Built for Endurance

At the heart of UCAN’s performance line is LIVSTEADY™— a patented, complex carbohydrate that digests slowly and delivers 75+ minutes of steady, sugar-free energy. No spikes. No crashes. No stomach issues.

Developed with input from Olympic coaches and endurance athletes, UCAN’s LIVSTEADY™ formula is trusted by marathoners, triathletes, and pro teams around the world.

Recommended UCAN Products:

• UCAN Energy Gels – Pocket-sized, easy on the stomach, and packed with slow-burning carbs for on-the-go energy
• UCAN Energy Powders – Clean, pre-workout fuel to keep you going strong from the start
• UCAN Protein + Energy – Slow carbs plus high-quality protein to rebuild and refuel after hard efforts
  
  

Every product is powered by LIVSTEADY™. Every product helps you train smarter, race stronger, and recover faster.

When to Use Slow Burning Carbs

• Before workouts or races (30–45 mins out): UCAN Energy Powder or Energy Gel
• During training lasting 75+ minutes: UCAN Energy Gel every 45–60 minutes
• Post-workout recovery: UCAN Protein + Energy to restore glycogen and support muscle recovery
  
  

Fueling this way keeps your body running on a clean, consistent energy source—no sugar highs, no crashes, no gut bombs.

FAQ: Slow Burning Carbs & Endurance Nutrition

What exactly are slow carbs?

They’re low-glycemic carbohydrates that release energy slowly during digestion, providing a longer, steadier fuel source than traditional sugar-based carbs.

Are slow carbs good for runners and cyclists?

Absolutely. They help maintain consistent effort and mental clarity during long training sessions or races.

How is UCAN different from other sports fuels?

UCAN uses LIVSTEADY™, a proprietary slow-burning carbohydrate, instead of sugar or maltodextrin. It provides clean, sustained energy without the GI issues or sugar crashes.

Do I need both slow and fast carbs?

Some athletes combine them. But many find that once they switch to UCAN’s slow carbs, they don’t need fast carbs at all until the final push of a race.

Will slow carbs upset my stomach?

UCAN is designed to be easy on the stomach—even in heat, long races, or tough training conditions. It’s trusted by sensitive athletes across sports.

Final Takeaway

Slow burning carbs don’t just help you avoid bonking—they help you train better, perform longer, and recover faster. UCAN’s LIVSTEADY™-powered fuels are changing the way athletes approach endurance nutrition—by providing steady, clean energy with no sugar and no crash.

Level up your long runs, rides, and races. Shop UCAN and feel the difference that slow release carbs can make in your performance.