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Glossary

Bonking: meaning and usage for runners

Bonking is the sudden energy crash runners feel when stored carbohydrate runs low, often making the pace collapse late in a long run or race.

Example

Example: At 30K of a marathon, a runner who skipped gels may suddenly slow from goal pace to a shuffle because they are bonking.

Why it matters

Bonking explains a specific fuel problem, not just low motivation. Recognizing it helps runners separate pacing mistakes, heat stress, and carbohydrate depletion after long efforts.

How runners use it

For runs longer than 90 minutes, practice carbohydrate intake before race day. Carry gels or sports drink, start fueling early, and adjust pace when energy drops sharply.

Related terms

Related resources

FAQ

What does Bonking mean for runners?

Bonking is the sudden energy crash runners feel when stored carbohydrate runs low, often making the pace collapse late in a long run or race.

Should beginner runners know Bonking?

Yes. Bonking appears in training logs, race instructions, and runner conversations, so knowing the basic meaning helps you act on the information.

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