Avoid Bonking: Common Mistakes in Race Nutrition & How to Fix Them

Nothing derails race day faster than hitting the wall—that dreaded moment when your energy levels plummet, your legs feel like lead, and every step becomes a struggle. This is known as bonking, and it’s most commonly caused by poor or insufficient nutrition and fueling. However, it can also result from excessive muscle damage, where accumulated fatigue and breakdown impair muscle function and performance. The good news? It’s preventable. Here’s how to avoid common fueling mistakes and keep your energy levels steady from start to finish.

1. Underestimating Carbohydrate Needs

Your body relies on carbohydrates as its primary fuel source during endurance efforts. If you don’t consume enough, glycogen stores deplete, leading to a crash.

SOLUTION: Aim for 60-90g of carbohydrates per hour during races lasting longer than 60 minutes. Our Endurance Fuel provides 20g of carbs per serve, making it easy to hit your target by adjusting your intake. Gels and solid foods can be added based on personal preference and requirements.

2. Neglecting Electrolytes

Sweating depletes sodium, potassium, and magnesium—key electrolytes that maintain muscle function and prevent cramping. Simply drinking water isn’t enough.

SOLUTION: Use an electrolyte mix with a balanced sodium-to-potassium ratio. Each serve of Endurance Fuel contains 500mg of sodium, allowing you to adjust intake based on sweat rate. Most athletes need 500-1,500mg of sodium per hour in hot or humid conditions.

3. Waiting Too Long to Fuel

If you wait until you feel thirsty, hungry, or fatigued to start fueling, it’s already too late.

SOLUTION: Start fueling early and consistently—don’t wait until mile 15 to take your first sip. Begin sipping electrolytes and carbs within the first 20-30 minutes and continue at regular intervals. I take a sip of my Endurance Fuel every kilometer and have a gel every 30 minutes to stay on top of my carbohydrate and hydration requirements. 

4. Experimenting with New Nutrition on Race Day

Trying out a new gel, drink mix, or fueling strategy on race day can lead to gut distress or poor performance.

SOLUTION: Train with what you race with. Use your race nutrition in long and intense sessions to ensure your stomach can handle it.

5. Overloading on Fiber, Fat, or Protein Before the Race

While these nutrients are essential in your daily diet, too much before a race can slow digestion and cause GI distress.

SOLUTION: Stick to low-fiber, carb-focused meals in the 24-48 hours before the race. Avoid heavy, high-fat meals the night before.

6. Ignoring Hydration Pre-Race

Starting the race dehydrated makes it harder to maintain fluid balance and performance.

SOLUTION: Preload with electrolytes the day before and drink 1-2 servings of Endurance Fuel 60 minutes before the start. This helps optimise fluid absorption and sodium levels before you toe the start line.

7. Relying Too Much on Gels Without Hydration

Gels provide quick carbs, but without proper hydration, they can cause gut discomfort and slow absorption.

SOLUTION: If using gels, always chase them with water or an electrolyte drink to aid digestion and prevent stomach issues.

8. Overlooking Muscle Damage as a Cause of Bonking

While nutrition is the most common cause of bonking, accumulated muscle damage can also play a role. Long races or intense efforts cause muscle breakdown, leading to fatigue, reduced force production, and increased cramping risk.

SOLUTION: 

• Fuel Properly – Maintain 60-90g of carbs per hour to spare glycogen and delay muscle fatigue.
• Electrolyte Balance - Ensure 500-1,500mg of sodium per hour to maintain muscle function. 
• Train Smart - Gradually build volume and intensity through your training block to avoid accumulating too much fatigue.
• Get Comfortable at Race Pace - Practice running at your goal race pace during training to help your body adapt to the effort and intensity, reducing fatigue on race day. 
• Recover Well - Prioritise protein intake post-race for muscle repair. 

Final Thoughts

Avoiding the 'wall' is all about strategy and consistency. Stick to a fueling plan that meets your personal carb, electrolyte, and hydration needs, and don’t wait until race day to test it. With the right approach, you’ll stay strong from start to finish.

Need a simple, effective fueling solution? 

Try Pulse Nutrition’s Endurance Fuel—formulated for sustained energy, optimal hydration, and race-day success. 🚀