If you’ve ever felt your legs turn to jelly on a ride and as if all the petrol just ran out of your tank, you’ve experienced the bonk. The dreaded bonk makes it impossible to finish a race or even just to make it home.
Although, in itself, not dangerous, the consequences of suffering the bonk are particularly dangerous if you’re riding alone or in an unfamiliar place. Plus you’re likely to consume a big pile of carbs or sugar to regain your energy so it will mess up your nutrition and cause weight gain.
All in all, it’s vital to take steps to make sure the bonk doesn’t happen to you during any kind of ride or race.
What is the bonk?
Put simply, the bonk is what happens when the body becomes completely depleted of glycogen. Without glycogen, your body has no more fuel to power effort so, instead, tries to burn fat. But turning fat into energy isn’t a fast enough process so you’re left severely fatigued or even collapsed.
The 48 hours leading up to a ride are the key time to carb load to ensure your glycogen levels are topped up. About 7-10g of carbs per kilo of bodyweight is enough so don’t go all out on huge plates of pasta, rice and potatoes.
Pre-loading carbs isn’t enough as it’s crucially important to top up glycogen stores to avoid the bonk during rides too. Sports drinks, gels and bars are easy to carry and consume on the go and 30-60g of carbs per hour is the recommendation of the Gatorade Sports Science Institute. Isotonic drinks containing about 6-7% carbohydrate are a great way to refuel while also rehydrating.
Caffeine is another energy boost but, again, don’t over do it – 2-3mg of caffeine per bodyweight kilo no more than every couple of hours is about right, which is the equivalent of a double espresso.
Lastly, recovery is just as important so you’ll want to eat low GI carbs and protein in the four hours after a ride. Think yoghurt, muesli and pasta rather than bananas and white bread.
Why is bonking funny?
Obviously, experiencing the bonk isn’t funny.
But talking about it often is.
If you’re not British, you might not realise that every time anyone says the word “bonk”, it provokes sniggers and maybe blushes.
If phrases like “Did you bonk?”, “I bonked”, and, worst of all, “I bonked hard” don’t make you giggle like an idiot, then you probably don’t know that in British slang “to bonk” is a particularly silly word for “to have sex.”
Circa the 80s “bonk” was a trying-to-be-worldly British pre-teen expression for pretending your knowledge of sex was somewhat sophisticated. It was eventually phased out in favour of “to shag” which is a terrible name for a haircut, a dance and a carpet as a result.
In running circles, “the bonk” is called “the wall” for which there has, as yet, been no smutty association. Unfortunately for cycling, school child smirks from some people are guaranteed whenever you say it.
At least now you know.
When Dave bonked
Honestly, I couldn’t stop myself giggling like an 8-year-old who just found out that Valencia has a traditional sweet bread called fartons when I typed that heading.
And I had to comment on the ridiculousness of the question when I asked Pro Cycling Outlet’s co-founder, Dave Walsh, for one of his best bonking stories (I giggled typing that too).
So, here it is, transcribed with much silliness: Dave Walsh’s best bonk.
“I was cycling in the mountains and got lost, very lost. I ran out of food, ran out of water after 8 hours riding and I bonked hard. I could see Girona in the distance so I tried to ride in a straight line towards it … and ended up somewhere in the woods when night came. And it was February so it was freezing. So I built a shelter, like Bear Grylls, and collapsed until dawn. The worst thing was that it turned out my shelter was only 300m from the road and I didn’t know until daylight. I was home in an hour – hallucinating, double vision, hypothermia – and none of my flatmates had realised I wasn’t back so I could’ve died out there!”
So, there you go. Don’t bonk in the mountains and heed the advice above.