Bonking on the bike – Michele’s experience during the Tour de France, 1984.

Bonking (or hitting the wall) – suddenly losing energy and the onset of fatigue resulting in a major performance drop. Usually caused by the depletion of glycogen in the body.

On the recent bike ride, I experienced the dreaded Bonk. Its interesting how your body reacts in situations like this and how simple preparation and awareness could have prevented this. Did some reading up on this and here is what I found out.

There is enough sugar in the body to last three minutes. The liver constantly releases sugar from its cells into the blood stream to prevent the sugar level from dropping. The liver has only enough blood sugar to last about 12 hours at rest. During intense exercise your muscles use sugar at a rapid rate. Your liver can run out of stored sugar and you bonk !

To prevent this there are various steps that we can take

  • constantly keep hydrating yourself thru the ride. Water or any energy drink would do.
  • electrolyte would be better than plain water. Rapid skin evaporation can impart a false sense of perspiration. And if you notice you loose quite a bit of salt on long rides. Replenishing this would be ideal
  • keep eating and fueling your body thru the ride.

Some interesting reads

[update: Lots of interesting links are pouring in from the readers. Have added them above. Thanks guys]

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About the Author

Rohan Kini

WHAT I LOVE ABOUT CYCLING I love riding my bike. Whether it's a simple commute, a high-intensity road race, a jaw-grinding brevet, fixie rides thru packed Indian city or a kick-ass technical single track – I love it all. Apart from riding bicycles, I love being all geeky and know everything there is to know about bicycles, technology, bike fit, and service. I started BUMSONTHESADDLE to share this passion for cycling. DISCIPLINE: Partial towards MOUNTAIN BIKING but love it all CURRENT BIKE(S): Specialized Rockhopper, Specialized Tarmac, Pure Cycles Original DREAM BIKE: S-Works Epic HT & S-Work Roubaix OTHER PASSIONS: Technology, Photography, Baking, Travel, and Reading

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