Bonk

[ColinJ]

I dare not type that !!

That's what anonymous browsing is for!

I was once asked to sort out a dodgy computer for somebody who was clearly unfamiliar with that concept. I was going to search for "Virus..." but only got as far as typing the 'v' before Google helpfully suggested that I might be about to type 'Vixen sluts in uniform'!

 

[IanSmithCSE]

Good evening,

Firstly, I am going to ignore those on ketone diets as I don't understand the ketone depletion process at all, although glycogen and ketones can be seen as functionally interchangeable to a large degree when all is normal, depletion is not normal.

It turns out that the body has a glycogen depletion prevention mechanism and I suspect that how this works will be at least part of the reason for different experiences.

In normal circumstances the brain extracts glucose from the blood to power it, the muscles convert their glycogen to glucose when needed to supplement their energy need when it can't be supplied from blood glucose.

When the muscle glycogen is depleted all of the required glucose is pulled from the blood stream and the liver responds by increasing the conversion of liver glycogen to glucose and releasing it into the blood. At some point a mechanism determines that the glycogen conversion rate is too high and reduces/supresses it.

There is no mechanism to tag glucose in the blood for use by the brain only or the muscles only.

Pure supposition here but when and by how much this suppression takes place would seem likely to alter the individual's experience.

• Only partly suppress the increased rate and do so early would see the individual getting hints that all is not well.
• Barely suppress the rate and only do so late on would see the individual going from all's fine to not enough glucose to move or think within a very short period of time.

Bye

Ian

 

[Biker man]

I dare not type that !!😃😃😋

 

[oldwheels]

It only happened to me once while still in my teens. We had slept rough in an old shed near Appin and being short of water did not wash the pan used for scrambled eggs properly and next morning made porridge in the same pan. It was so horrible we could not eat it and set off at about 5AM and could not find any food till Inveraray. Getting up the hill before Inveraray nearly did for us with the lack of any food since the previous day.

 

[yello]

It's never happened to me. Not in the dramatic way I read other people describe it,

Ditto. I've read numerous accounts over the years on here but can't honestly say I've suffered it myself. Maybe some are more predisposed to it than others.

 

[yello]

I rarely carry food on a ride less than, say, 25 miles and whilst I always take water I often don't touch it during the ride unless it's really warm. I do it all kinds of wrong but so far have got away with it.

Ditto again.

I'd go out for 25 - 30km before breakfast without problem. And do a 100km with a banana and a flapjack. Club mates have commented on how little I ate (I make up for it after the ride I guess!) So I reckon, like I said, some folk just don't need to fuel as often.

 

[gbb]

Happened to me a couple times In the past and I'm not sure I saw any warning signs (there were doubtless subtle ones i missed)
Both probably on my old 50 mile hard rides, both times about 5 miles from home and simply energy crashed, maybe 2 minutes warning then all you want to do get off the bike and sit on the verge, its awful.
I always thought it was probably (unwittingly) poor preparation /fuelling, I'd never eat anything special, just a normal light breakfast, which 99% of the time was fine but I guess if you were just a bit under par it might tip you over the edge.

 

[All uphill]

Ditto. I've read numerous accounts over the years on here but can't honestly say I've suffered it myself. Maybe some are more predisposed to it than others.

I'm sure you are right @yello .

I seem to be at the other end of the spectrum although I do get lots of warning rather than a sudden crash. When I get wobbly and weak I have often been asked if I am diabetic, but my GP has confirmed I am not.

I remember standing in Worcester with a map in my hand completely unable to work out which direction to go, and not having the sense to just stop for a while and then eat. I still owe thanks to the young man who got me a cup of tea and a piece of fruitcake!

 

[Rocky]

Bonk….is for wimps. Last year I cycled Lands End to John O’Groats in one go. My only sustenance was half a raw carrot.

 

[bagpuss]

The missus got the hunger knock when we were touring on our tandem many years ago . I end up riding it home 60 miles solo, whilst she got a lift with some friends .

 

[ColinJ]

I suddenly bonked and ended up lying in the middle of a singletrack road on Mull once! A very alarmed couple in a car stopped to ask if I was ok. Well, I thought that they were concerned about me - maybe they actually stopped to drag the corpse out of the way!

I wrote a story about the first time the bonk got me... The Trauma of Trawden.

 

[yello]

Bonk….is for wimps. Last year I cycled Lands End to John O’Groats in one go. My only sustenance was half a raw carrot.

I kinda knew I was queueing that up! I was anticipating the '3 Yorkshire men' take.

Seriously though, I'm not doubting anyone. I'm just saying I personally haven't suffered with it as others describe it. Nearest I think I got was on PBP when I made the curious decision to not have breakfast at Carhaix before the section to Brest. It was a haul and I was running on empty when I got there, but nonetheless didn't experience the classic bonk symptoms others have had.

 

[Ming the Merciless]

Bonk….is for wimps. Last year I cycled Lands End to John O’Groats in one go. My only sustenance was half a raw carrot.

Was this the carrot?

 

[fossyant]

Those who have never bonked, obviously haven't been trying hard enough.

 

[fossyant]

I've had it at times - I can feel it coming on - I'll usually start to get 'flashing lights and a 'target' appear in my sight, that's the early indication I need to eat/drink something. Used to be completely spent after 50 mile TT's so much so, I could hardly pedal after I finished (bear in mind I was doing 25mph steady before that). I mainly suffered when I was starting out as you don't know how to fuel properly. I still struggle to 'eat' on the go, can't eat anything dry, so often just stick to carb drinks.