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Blowing up or bonking whats the difference?

3K views 17 replies 12 participants last post by  mtbykr 
#1 ·
Exploding or bonking whats the difference?
I have had rides where I just slow down sometimes to the point of not riding anymore. I asume that is bonking.
I have blasted up climbs to have my legs and lungs give out. Is that blowing up?

Just wondering.

Thanks
Mike
 
#2 ·
My interpretation is this:
Bonking-running out of energy due to lack of food and/or sugars to fuel your muscles. Usually is a gradual process and can be reversed with a quick dose of energy drink, gel, or bar.

Blowing up-Riding at your maximum heart rate for an extended amount of time until you simply cannot recover and start hyper-ventilating (ie Blowing the engine). Requires a rest period to get your heart rate and breathing back to normal.
 
#5 ·
I blow up nearly every ride!! haha

I am pushing myself further and further...but man I am just plain cardio outta shape!! My climbing and general riding skills are improving...which is helping on the amount of energy I use...but it still is not a easy, "Oh, let's go climb this huge hill"...I know I have to stop after any intense climb...
 
#9 · (Edited)
As someone who does long rides, I've experienced the dreaded "bonk." Bonking is when you hit the limit of your energy and hydration....you don't have the fuel or fluids keep up your level of energy and you have to throttle way back or stop. It will take a fairly long time to get back up to pace if you "bonk"...often it means stopping for fluids and energy and then letting your body process both before trying to ride at any sort of elevated pace again. For a car analogy, you've run out of gas or boiled over...gonna need to walk to get some gas or water.

Mtnbiker72 is correct in how he defines "blowing up." You're maxing out your cadence (meaning you're starting to push into anaerobic work) and heart rate...you get to a point where you're body just cannot get rid of the metabolic wastes fast enough and it shuts you down. You still have the energy and you can be perfectly hydrated, but your body is backlogged with the wastes. A little rest to get the heart rate and breathing back under control (the body needs oxygen to break down and eliminate some of these acidic anaerobic wastes) and you can normally continue. For the car analogy, you'd have to think of it as you've hit the red line and a fail-safe kicked in to shut down the ignition until things cool off a bit. Get it stopped, put it in park, turn the key and you're back up and running.
 
#10 ·
I would assume blowing up (as in my example above) is more common with out of shape rider's such as myself...

I always take energy bars, eat a good breakfast a few hours before riding, and probably carry more water than I need for each ride...so I don't really think I have felt the effects of bonking yet...The max hours of riding I have done on one day is like 3 hours...
 
#11 ·
Blowing up doesn't have to be an out of shape rider event. Many riders try to push themselves harder and sometimes over do it. I think it is more prevalent with high performance riders, to be honest. There were some serious concerns that Lance Armstrong was going to do it a lot with his high cadence style.

Sure, many recreational riders have blown up, but often it is because they are trying to keep up with a friend or another rider...riding solo, most will back off before they blow up.

I've managed it once... I was racing home after work as there were places I needed to get to (quite urgently) and I needed the car to do it. Well, even with stop lights, stop signs, traffic and such I shaved about 4 minutes off my "normal" commute (on a 5 km ride, that is a lot of time). Just as I got home, the wheels fell off....I couldn't have gone another block at any sort of pace for about 10 minutes.

The only time I've come close on a long ride was with a pretty nasty hill at the 78 km mark of a 90 km ride. Don't know what the grade of the hill is, but I had to gear it back and just "sit and spin" for a bit.
 
#12 ·
Alright, from my 24 years of serious endurance competition, I define them this way:

Blowing Up - going in to oxygen debt so far that conditions and conditioning don't allow you to back off to the point that you can maintain a half decent pace. If you can slow down somewhat, go back in to aerobic state and then regain a reasonable race pace then you haven't blown up. If you go so far in to oxygen debt that you have to drop to a training pace for the rest of the race, then you've had a classic blow-up. Blow-ups happen when you are trying to race way above your head. This doesn't apply so much in intense mtn biking as you tend to go to max oxygen debt on each climb and recover afterwards. The whole race is a yo-yo. (referring to hilly technical courses like the one I train on)

Bonking is when you have depleted your muscle's glycogen store and your body moves on to pulling glycogen from the liver. When the liver is depleted your blood-glucose level plummets and you get dizzy, weak, and even your brain starts to shut down. You can't speak without slurring your words. I had it happen on a bike ride once and couldn't continue to spin the bike at 5mph. I had to stop and eat one saltine cracker, and 2 raisins that had been long forgotten in my pocket. This got me home. Generally a well-trained athlete will not bonk because the body begins metabolizing fat long before glycogen is depleted and there's a smooth transition from glycogen to fat for an energy source. If you bonk, you're not well trained.
 
#13 ·
Psycho Mike said:
Sure, many recreational riders have blown up, but often it is because they are trying to keep up with a friend or another rider...riding solo, most will back off before they blow up.
I ran into that on the first race I did. I was just trying to follow someone through a tighter section, not wanting to hold up the people behind me. My heart rate was in the high 180's by the time I found room to let them by...
 
#15 ·
jyeager said:
Alright, from my 24 years of serious endurance competition, I define them this way:

Blowing Up - going in to oxygen debt so far that conditions and conditioning don't allow you to back off to the point that you can maintain a half decent pace. If you can slow down somewhat, go back in to aerobic state and then regain a reasonable race pace then you haven't blown up. If you go so far in to oxygen debt that you have to drop to a training pace for the rest of the race, then you've had a classic blow-up. Blow-ups happen when you are trying to race way above your head. This doesn't apply so much in intense mtn biking as you tend to go to max oxygen debt on each climb and recover afterwards. The whole race is a yo-yo. (referring to hilly technical courses like the one I train on)

Bonking is when you have depleted your muscle's glycogen store and your body moves on to pulling glycogen from the liver. When the liver is depleted your blood-glucose level plummets and you get dizzy, weak, and even your brain starts to shut down. You can't speak without slurring your words. I had it happen on a bike ride once and couldn't continue to spin the bike at 5mph. I had to stop and eat one saltine cracker, and 2 raisins that had been long forgotten in my pocket. This got me home. Generally a well-trained athlete will not bonk because the body begins metabolizing fat long before glycogen is depleted and there's a smooth transition from glycogen to fat for an energy source. If you bonk, you're not well trained.
I would agree with this...I would however disagree with with the last statement. You can bonk if you are well trained. I have seem many adventure racers bonk (and they are well trained) after several days out strait.....it can happen, you body can only go so far! It's happened to me a few times in my life, and without a doubt the worst time i have spent in the saddle!
 
#16 ·
I stand corrected. I hadn't been considering the extremes that you are mentioning. Perhaps if I modified my statement to say that you won't bonk if you are properly conditioned for the effort at hand?

If someone were trained specifically for these ultra events, then they shouldn't bonk...however, how do you train for some of these? Very few people are going to be able to train their bodies to cover hundreds of miles per day or to go for 12+ hrs per day for many days on end. So I guess I'd say in that case their bodies weren't prepared...or they failed to eat enough. In that case it's simply chemistry and physics...bonking might occur.

So in a way, I think we are probably both right.

Thanks.
 
#17 ·
Yeah, I can agree with the modified version. This past year, I did a bigger "tour" than the one I bonked on and had lots left in the tank. Part of it was training, the other part was eating and hydrating properly. The properly trained, properly nourised and hydrated rider shouldn't bonk...others might :)
 
#18 ·
ok

jyeager said:
I stand corrected. I hadn't been considering the extremes that you are mentioning. Perhaps if I modified my statement to say that you won't bonk if you are properly conditioned for the effort at hand?

If someone were trained specifically for these ultra events, then they shouldn't bonk...however, how do you train for some of these? Very few people are going to be able to train their bodies to cover hundreds of miles per day or to go for 12+ hrs per day for many days on end. So I guess I'd say in that case their bodies weren't prepared...or they failed to eat enough. In that case it's simply chemistry and physics...bonking might occur.

So in a way, I think we are probably both right.

Thanks.
Ya...the races where i see it the most are longer races. These races are up to 5 days/450 miles. So def on the extreme end of the spectrum. I would assume that most "bonks" happen when people do more (work harder) than what they are used to or have trained for. I think that a lot of the problems stem from people not knowing how to properly hydrate and fuel themselves..that was def my problem. I learned a lot from Hammer Nutrition's guide to success...

http://www.hammernutrition.com/downloads/fuelinghandbook.pdf

This was eye opening to me and i've yet to find someone who has used this (and hammer products) and been disapointed! I've yet to dehydrate and/or bonk after reading this.
 
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