What is Bonking?

Bonking, also known as hitting the wall, is the sudden and dramatic loss of energy that runners experience when their glycogen stores become depleted. It typically occurs around the 30-35 km mark in a marathon.

Why Does It Happen?

Your body stores glycogen (carbohydrates) in your muscles and liver. During prolonged exercise, these stores get depleted. When they run out:

• Blood sugar drops rapidly
• Your legs feel like they're filled with cement
• Mental fog sets in
• Every step becomes a monumental effort

How to Avoid Bonking

1. Proper Carbo Loading - Increase carbohydrate intake 2-3 days before race day
2. Fuel During the Race - Take energy gels every 30-45 minutes
3. Pace Yourself - Don't go out too fast; aim for negative splits
4. Train Your Gut - Practice nutrition strategy during long runs

Signs You're About to Bonk

• Sudden fatigue that feels different from normal tiredness
• Difficulty maintaining pace despite effort
• Negative thoughts flooding your mind
• Physical symptoms like dizziness or nausea

The wall isn't a myth—it's very real. The key is training your body to use fat as fuel and having a solid nutrition plan. — Every experienced marathoner