Bonking is running out of glycogen. Your body is forced to switch to fat for energy stores, which reduces the level of effort you can exert. No matter what you do, you just can't pick up the pace, your heart rate drops, and you really, really want to eat. Anything.

You know you have bonked when all you can think about is food.

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"Go yell at an M&M"

running out of energy due to not eating enough....in laymans terms, feels like shit.

This is bonking...my budrow Jekyll on his Trek...

"I'll trade you this bike for a fucking Snickers bar...."

That's bonking.

Spot

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Taco cat spelled backwards is....taco cat.

feeling good...feeling good...feeling good...BAM!!...you hate the world and everything in it. That's a bonk.
The previous posts are a bit more precise, but this conveys the "feeling" of a bonk.

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Brian Grasky
Grasky Endurance: World Championship Triathlon Coaching; Professional Training Camps
RETUL fitter, Biomechanist, USAT Level 3 Coach, USAC Level 2 Coach

When I'm getting dropped and start to cry. Really, it's happened twice. For no reason, riding up a hill, can't hang on, start to get all emotional, hate everything about cycling, start to cry.

When you're running and not in pain, but you just can't run anymore. Your heart rate is low and everything seems to be in slow motion.

Hmmm...my wife seems to bonk about every 28 days!

Hmmmm . . . based on the descriptions so far, it doesn't sound like I bonked.

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Mike Sparks


I have competed well, I have finished the race, I have kept the faith.

You know you have bonked when you pull into a gas station while on a ride, weakly stagger in and buy a king size snickers and eat the shit out of it as if you hadn't eaten in 4 days.

Bonked during the run of my last half IM, as others have described, couldn't get my HR up to run. Also become very apathetic. Next time I do a race sponsored by HEED I'll bring a fuelbelt.

Another bonk during a long (175 mi or so) ride last summer, 15 miles to go and the bottom of the barrel dropped out of my energy reserves. Couldn't get HR up, felt dazed and numb rolling along. Out of curiousity I 'hammered' up a short climb and got my HR up to 145 (my LT HR is somewhere in the 165-170 range), practically threw up. When I got back my friend said I looked pale and that they had just finished eating a huge stack of grilled cheese sandwiches.

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All we have to decide is what to do with the time that is given to us. ~Gandalf

Bonking is when your fuel stores are low, and either your legs or your brain quit. It's like your car running out of gas. There's only way to remedy the situation, and that's with calories. High glycemic index foods like snickers and coke are my food of choice in such circumstances.

But what it really means is that you totally screwed up your nutrition plan. Now it's possible that something like gastric issues were to blame, but most people just make poor choices.

I once called for a ride from a rest stop 1 mile from my house; I just flat couldn't cycle another inch.

Interesting article from RW here: http://www.runnersworld.com/...-301--6263-0,00.html

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Steen Rose
http://www.athletesontrack.com

Only REALLY bonked twice in the last few years, both due to undereating.

First was on a training ride, was going to do a quick hour ride and was feeling good, went further than I should, an hour turned to 3+ without anything but water and I was tired from a run earlier in the day. Had trouble holding 15mph on the flats for the final miles home, only thought about eating, barely made it up the hill home and collapsed in the kitchen eating everything in site and drank a 2 liter of coke.

Second was at a half this summer, wasn't taking in as much as I should during the run, was on a decent (for me) pace to run about 1:3x and then bonked hard at about mile 11.5. Lost 10+ minutes the last two miles, including a spot where I stood by the side of the run course and almost just laid down despite being less than a mile from the finish, then made it to the finish only to crest a small rise about 200yds from the finish (which was all downhill) and just stopped and stared at the finish line for what felt like forever. Almost laid down there and just rested for a while, saw a guy coming around the bend and somehow ran to the finish slightly ahead of him only to collapse in the grass after they got my timing chip off begging a volunteer for cokes and gatoraide. After laying there for about 20 minutes and eating I finally could get up.

Lots of people through out the term bonk all the time, and there's plenty of times I've slowed down or tired in races or training, but those are the only times I truly 'bonked' and felt that awful, hungry, just plain dead etc...

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Your lucky mine seems to bonk every 14 days!

Just Google "bonking" and see what comes up...

Should be fairly informative.

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Pain is the pruifier...

Don't google bonking at work; it came up with an inflatable sheep.

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Steen Rose
http://www.athletesontrack.com

http://forum.slowtwitch.com/...r%20alberto;#2249030


If you read the above thread you can see that not everyone defines "bonk" as complete glycogen depletion -but most of everyone does.
The "bonk" occurs at complete glycogen depletion, at which time your energy substrate for working muscle becomes almost entirely fatty acid metabolism via beta oxidation. Glucose is still produced via gluconeogenesis within the liver - to the level to support vital tissues aka the brain. You can only produce a limited amount of calories per unit time via beta oxidation which (probably among neuro-hormonal controls) forces you to throttle back and produces all of the symptoms.

If you have never had an overall lack of energy at the IM distance you most likely haven't experienced what everyone describes as the "bonk" and you are either really lucky, or have a gifted GI tract and metabolic system of a combination of both.

A good recipe to experience what everyone is describing would be to do a 3 day carb depletion while maintaining the intensity and duration of your workouts.
For safety I wouldn't suggest you ride the third day though.

Report back, because I'm pretty sure that you are missing out on something that 90 some odd percent of IM finishers have experienced - and we would like you to experience it too.

Kevin

It's a fast progression, but if you keeping pushing:
Legs get really, really heavy, KK doughnuts seem like the best thing man has ever invented
Holding a correct line becomes difficult
Turns become rediculous because your judgement is clouded (begin to feel like drunk driving) & you can't figure out where to brake
People will tell you this is when you begin to look like a rag doll
Tunnel vision sets in & focus is difficult
Just turning over the pedals and remembering why you want to turn them over is damn near impossible
It's over Johnny

I have also lost time & memory. Not a good place to be in. Only gone beyond 3rd on the list once, bad, bad news.

Mainly it's because of stupidity. I like the idea of a "central governor" but an honest to god bonk seems to be a problem. You do shut down before you die, but you are pretty far down the curve.

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Brawndo's got what plants crave. Brawndo's got electrolytes. And that's what plants crave. They crave electrolytes. Which is what Brawndo has. And that's why plants crave Brawndo. Not water, like from the toilet.

Oh yeah, and then there was the time that I stopped at a light and could not clip back in for about 3 blocks. Took me another mile or so to figure out that I was bonking.

The feeling is something like how you would feel after 36hrs w/o sleep....i.e. just no energy, hard to focus, irritable, etc.

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ECMGN Therapy Silicon Valley:
Depression, Neurocognitive problems, Dementias (Testing and Evaluation), Trauma and PTSD, Traumatic Brain Injury (TBI)

Do you guys find that sometimes you bonk hard & deep, and other times it's a bit quicker and less energy sapping?
Like, there are those times..it's hot & wet, you're in there for the hard yards and you're like "oh man here we go again...", all the
rest is a blur and you come out the other side with your shirt on inside out and backwards and someone elses underwear on.....
Other times it can kind of sneak up on you and you're thinkin' "oh man i reckon i might be in for just a quick one here" and you're in and out of that
bonk like Tiger in a LV cocktail waitress..........
Just seems to me like sometimes you bonk deep, like all the way and hardcore...and other times you're just like, in-out-in-out, repeat if necessary...

Capiche?

I almost never bonk in a running race or triathlon, because I normally taper the week before and carbo load, especially two days before. I've run 13 marathons (5 under 3 hrs) and did Kona in 13:07 23 years ago...never bonked.

Last Saturday I ran a half marathon. I had run 10 miles the Wednesday before and biked Thursday. Didn't carbo load until the day before...Friday. I hit the wall at 11 1/2 miles. Had to walk twice in the last mile and felt wobbly. Staggered across the finish line at 1:57. Not a good feeling. I grabbed a bagel and started gobbling it. Never did that before. Usually I don't feel the need to eat for a while. So, I learned a lesson.

Part of this may be due to age. I'm 63. When I was 40 I could run a fast marathon on a bagel eaten 3 hours before. At Kona, I only sipped a little Exceed a few times on the run. (I had eaten on the bike) We didn't have gels, etc., back then. I was strong to the finish. Now, I need to eat during a bike as short as 50 miles.

Once bonked on a ride 40 miles from home in the desert. Went from 25 mph - 6 mph in a matter of a minute then could not keep the bike upright, literally fell over. I must have had a little food on me cause I made it back but I can't remember how. Learned my lesson.

From that description it sounds like the difference between running out of muscle glycogen vs running out of blood sugar. During the former your pretty much hosed until your calorie intake exceeds output for awhile. The latter is reversible faster via sugar. Blood sugar is the only form of energy your brain can use, how lack of it affects you might vary from person to person (I get really apathetic and wonder wth I'm doing, some people get irritable).

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All we have to decide is what to do with the time that is given to us. ~Gandalf

As others have said, the low hr and low power or pace is a really good indication.

it feels like slow motion, it does not hurt, but you just do not seem to move forward anymore. With extreme bonks you can start shaking uncontrolable, feeling dizzy and you can even faint. If you stop and eat or drink a bit of sugar you are feeling normal in 5 minutes. But that normal feeling usually disappears quickly if you start to move again.