Bonking, also known as hitting the wall, is a condition where a runner runs out of fuel, causing their muscles to stop functioning properly. It is a state of complete exhaustion, characterized by nausea, extreme weakness, poor coordination, dizziness, shakiness, and cognitive problems. There are two main types of bonking: the muscle-glycogen bonk, which occurs when the body's glycogen stores are depleted, and the blood-glucose bonk, where the body is fine but mental strength deteriorates.


  1. Causes: Bonking mainly occurs when the body runs out of glycogen, an essential energy source stored in muscles and the liver. During extended running, these stores can get used up, leading to a decrease in blood glucose levels and the feeling of exhaustion.
  2. Prevention: To avoid bonking, it's crucial to fuel your body correctly. This means consuming a mix of carbohydrates, fats, and proteins before, during, and after your run. Staying hydrated is also essential, as it helps in nutrient absorption.
  3. Handling Bonking: If you start to bonk during a run, consuming simple carbohydrates like sports drinks or energy gels can quickly raise your blood glucose levels. You might also need to slow your pace or take walking breaks to recover.
  4. Strategy for Long Runs: Proper nutrition, hydration, and pacing are key to preventing bonking on long runs or races. Preparing your body for the physical demands of running can help you maintain energy and perform your best.

In summary, bonking is a runner's challenge during long and intense runs, but with the right nutrition and hydration strategies, you can minimize its risk and manage it effectively if it happens.


Some symptoms of bonking during running include:

  1. Nausea: A feeling of nausea can be a sign of depleted glycogen stores and insufficient energy supply.
  2. Extreme weakness: Runners experiencing bonking may feel extremely weak and struggle to maintain their pace or even get up from a seated position.
  3. Poor coordination: Bonking can lead to poor coordination, making it difficult for runners to navigate their environment and perform basic tasks.
  4. Dizziness: Runners who are bonking may experience dizziness, which can make it challenging to stay on course and maintain their pace.
  5. Shakiness: Shakiness, or uncontrollable tremors, can be a symptom of bonking, as the body struggles to provide enough energy to function properly.
  6. Cognitive problems: Bonking can lead to cognitive impairment, making it difficult for runners to think clearly and make decisions during the race.
  7. Overall miserable feeling: Runners experiencing bonking may feel extremely uncomfortable and unhappy, wanting to stop the race or training session.

It is essential for runners to be aware of these symptoms and take appropriate measures to prevent bonking, such as proper fueling, hydration, and pacing during long-distance runs or races.