When it comes to endurance events, the term "bonk" is synonymous with "hitting the wall." Cyclists experience this sudden energy depletion when their glycogen stores are exhausted, leading to severe fatigue, dizziness, and an inability to continue riding. This article covers everything you need to know about bonking—from causes and symptoms to prevention and recovery strategies.
What Is Bonking in Cycling?
Bonking occurs when your body depletes its glycogen reserves during high-intensity exercise, leaving muscles and the brain without sufficient fuel.
Key Symptoms of Bonking
- Nausea
- Dizziness
- Shakiness
- Extreme fatigue
- Cognitive impairment
- Poor coordination
Primary Causes
- Glycogen depletion: Intense cycling burns glycogen faster than fat.
- Inadequate fueling: Skipping pre-ride meals or mid-ride nutrition.
- Dehydration: Exacerbates fatigue and cramps.
👉 Boost your endurance with these expert tips
The Impact of Bonking on Health
1. Muscle Loss
When glycogen runs low, the body breaks down muscle protein for energy, leading to weakened performance.
2. Immune System Suppression
Overtraining increases susceptibility to illness due to elevated stress hormones.
3. Cognitive Decline
Low blood glucose impairs decision-making and focus, critical for safe cycling.
4. Dehydration Risks
Electrolyte imbalance from sweating worsens fatigue and cramping.
How to Prevent Bonking
1. Fuel Smart
- Pre-ride: Eat carb-rich meals (e.g., oatmeal, bananas) 2–3 hours before cycling.
- During rides: Consume 60–90g carbs/hour via energy gels, bars, or sports drinks.
2. Hydrate Properly
- Electrolyte drinks: Maintain sodium/potassium levels.
- Carb mixes: Opt for drinks with 3–4% carb concentration for optimal absorption.
3. Pace Yourself
- Avoid starting too fast; aim for steady effort (50–60% FTP).
- Use a bike computer to monitor speed and heart rate.
4. Train Strategically
- Fasted rides: Adapt your body to burn fat efficiently.
- Double sessions: Improve glycogen management with back-to-back workouts.
👉 Explore high-performance hydration solutions
What to Do If You Bonk
- Stop and refuel: Consume fast-acting carbs (e.g., juice, gels).
- Hydrate: Sip electrolyte drinks.
- Rest: Allow 24–48 hours for full recovery.
FAQs About Bonking
Q: How long does recovery take?
A: Typically 24–48 hours with proper carb intake and rest.
Q: Can bonking be fatal?
A: Extreme cases may lead to coma, but timely refueling prevents severe outcomes.
Q: Do men bonk more than women?
A: Yes, due to higher muscle mass and faster glycogen depletion.
Final Thoughts
Bonking is preventable with proper nutrition, hydration, and pacing. Prioritize carb-loading before long rides and listen to your body’s signals to avoid the dreaded "wall."
Stay fueled, stay strong!