i understand what it manes to bonk but have never experienced it yet.
my question is what exactly happens? is it dehydration or exhaustion or something else.is it mental, physical or both.
this thread is open to so much misinterpetaion…

Wiki

no more juice in the tank. You've run out of energy reserves and your muscles are now burning fat stores. It's a horrible, horrible feeling and very inefficient. Don't do it.

you have zero energy – limbs become heavy , vision goes blurry – you just want to sleep

of course depends how far you want to push your self ….

It not fun!

once its happened you'll know about it. its the worst feeling to have when your on a bike imo

Mental and Phyisical IME. lack of food probably, pushing too hard for too long as well. total exhaustion, Its a terrible place to be on a bike….your legs feel totally dead, I get the shakes, can't think straight, any slight hill reduces you to a total crawl. Its only happened twice, and I now do everything I can to stop it ever happening again

It's pretty much as Warton describes for me. Last time it involved me getting off and lying in the bushes only 500m from home, because I really didn't think I could go on.

Its awful

Lack of glycegen (sp) in the body so basically your body is breaking down the fat to fuel you. This is a very LONG process for the body.

It's a lot like love. If you've never had it, you'll never know.

Would it not be effective for loosing the fat as a way of weight loss?

Only happened once to me and as above it's horrible.

Shorty121 I would rather be fat.

yes but it's such an awful place to be you'd have to be properly butch to do it for very long. It's probably quite damaging too.

As above, even when a hard man like me 😉 gets it, it's an effort just to fall off the bike and get some food down.

Its ace. Just like having a hand shandy but more involving…:)

ask yer mum!

Can't believe everyone has answered this seriously. Anyway, I hope I'm the first to say…

"Ask your dad to tell you about the birds and the bees."

Some of the above responses are funny if you take the OP's question the wrong way though.

Damnit

i must say – its something i do once a year not on purpose but it does establish a nice base level for knowing where im at!

its shit at the time but when you look back you know you gave it your all !

It's really really really unpleasant.

Don't try and do a solid days riding with no brekkie or food with you, bad things happen!

any slight hill reduces you to a total crawl.

Unless you're being literal – if that's what you think you've never bonked properly 😀

The one time I had total bonk on a bike, merely thinking about any slight hill made me sit down and cry 😉

Seriously, there were some very good articles about 'The Bonk' – experiences and the physiology of bonking – in a volume of the mag a couple of years back. My favoutrite was the WC racer chasing down the lead group as he entered the last lap, hitting the wall, and finally losing about 40 minutes on the lead group in the final 25 minute lap. That's when the man with the hammer has properly struck.

It takes a LOT of mental strength to keep going once you have bonked. They only damagae I think you can do would be when youre tired and possible of straining due to not thinking?

You can keep hydrated through water but thats not enough. Your body needs sugars to keep going and fuel.

Its happend to me once and I wont let it happen again.

I'm really worried im gonna do it on the road bike, im new to road and I just know im gonna end up bonking a long way from home and end up delerious and dribbling at the side of the road. Current precautions are using energy drinks not water and taking a snack bar along

just eat. eat eat and eat. if you are worried then 'a' snack bar isnt enough.

take LOADS of food. if you dont eat it then dont worry. little and often. hydrate well before hand. eat before hand. eat and hydrate during.

Very Grim feeling, had it quite a few times over the years.

Last time I had it was Sunday in the Wiggle Enduro six. Got it after about 4.5 hrs but "did" two "SIS smack Gels" and a nearly a full bottle and got upto speed again. As trail-rat says its how far you want to push yourself, I wanted it bad so nailed myself for the last 2 hrs or so, its also alot to do with how menatlly tough you are as well. Like the survial instinct-Curl up and die or get up and fight. TBH I am still feeling the effects now though, I dug a bit too deep, 11 laps of that was harsh with limited MTB training. Still loved it 🙄

First time it happened to me I had to walk back to my car, almost killed me.*

When I got there the only food I had was a baguette and a mars bar multipack – before I knew what was going on I had slapped three mars bars in the baguette and downed it. Bad, bad times…

*I may not literally have been dying, sure as hell felt like it though

it's horrible.

your body needs sugar, without it you can't even burn fat*.

you can exercise for about 2 hours before you run out of sugar, sometimes a bit more, usually a bit less. It's a bit like someone's pulled the plug on you, and it can take days to recover from.

everything turns to 5h!t when you've bonked; it's very hard to concentrate, and your moral collapses.

(*you can, but it doesn't work very well at all)

for years i thought the way to beat it was to man up and train harder. i'm an idiot though.

ride bikes? – eat cake!

Shorty: No – once you've bonked you can only burn fat by also burning protein; your body has to eat it's own muscles if you want to continue. you will lose weight, but slowly, you'll also lose muscle mass, and you'll have a very unpleasant time.

You need to eat the correct foods though and in the corerct way.

Before a ride eat stuff thats low GI i.e so it drips into your system. When youre out you want stuff that is high GI so you get it quickly i.e when you need it.

There is no point eating a full fry up and then having pork pies whilst out as that will do **** all.

They only damagae I think you can do would be when youre tired and possible of straining due to not thinking?

I'm not sure (this is pure guesswork to be honest) but I suspect being hypoglycemic for extended or repeated periods could have long term affects on your brain which obviously needs energy to run as well. Dunno. It'll certainly have an affect on someone's thought processes, just doing it once or twice is enough to make you go mental.

Issue 47, Feb last year FWIW

If you've ever had it, full or partial, you'll want to avoid it. I occasionally do longish rides (for me) of 4-5 hours with minimal food / just smart water to see what i can manage before it starts to set in, but trust me, that 4-5 hours of riding never takes me more than about 3-4 miles from home so I can head back before I get it proper. And to avoid it on long rides I have to force myself to eat stuff by the watch – half a bar every half hour, a gel every hour, and energy drink in the bladder. Might be excessive, I'm not risking it though.

You will eat ANYTHING, and i mean ANYTHING to get some energy back. Dried mouldy bread, 2 year out of date energy bars, small rodents….

Happened to me when I was a young teenager out with a road club. I just came to a halt like a toy running out of batteries. I was about three miles from home, but I ended up just sitting at the side of the A41 on a raised manhole cover unable to move.
Some of the guys rode off and came back with Mars bars and dextrose tablets. Took a while to get going even then another rider rode with me with his hand on my back pushing me along.
No mobiles back then to call mummy.

I still see that man hole cover when I drive into 'that London' 👿

My worst 'bonk' was after a massive ride into the Peak, I was in Buxton and still had to ride over the Cat & Fiddle to Macclesfield (a not inconsiderable stretch of hilly road). I walked into a petrol station, fell over pulling a bunch of stuff with me, bought a packet of choclate Hob Nobs and 2 litres of coke (brain processes not operating normally). I ate and drank the lot and rode home. I was then very ill for a week. 😆

yep then follows a crawl into a local shop/garage to buy crap, then stuff your face with as much junk as possible..

You will eat ANYTHING, and i mean ANYTHING to get some energy back. Dried mouldy bread, 2 year out of date energy bars, small rodents….

As one of the articles also suggested, I'm pretty sure I looked in bins hoping for a partially eaten discarded ginsters.

bigyinn
I'm sure someone I know ate grass he was so bad. I'll call him

Them were the days.

ruining the 'bonk to lose weight' idea i should think…

kenneththecurtain – Member
before I knew what was going on I had slapped three mars bars in the baguette and downed it.

Sounds tasty, if a little dry. Add some ketchup or mayo and you could be on to a winner with that up here in Scotland.

only if you fry it and serve it with chips.

mayonaise? – that's like a salad then?

Its not simply your body going from Glycogen to Fat. You burn both during exercise…pure carbs when going MAX.

Its really bad for you training wise and will take at long time to get back from it.

I haven't hit the wall since uni….Out in Hanchurch, Stoke and some ways home. Felt like death. Didn't have energy to cry. Ate the world when I got back and waiting intill the deathly feeling had departed.