Is it bonk or just unfitness?

tozi1

Trying to improve my bike fitness- regular rides of 25 miles or so -on a 35 mile ride,two thirds through after a lunch break,seemed to run out of steam,brain to legs,need more power,legs,nope.Had a flapjack at the start and felt fine until after lunch,just wondered if you can tell between bonk and lack of fitness/miles in the legs,I.e. Do I need to eat more regularly or probably just ride more? Thanks.

diamonddog

Lunch on a ride of that distance :shock: Too much food IMO and yes ride more.

danlikesbikes

Think I'm not understanding but can't tell if your saying you had lunch, then had a flap jack followed by your ride, or you skipped lunch ate a flapjack then went out for a ride.

Either way would suggest you eat a snack (something good) pre ride but about an hour before, make sure your hydrated as it's easy to forget if your at work and get out and ride.

With fitness, good food & enough fluid you should be fine, miss the last 2 and you'll struggle to obtain consistent progress with the first.

diamonddog

I read it as flapjack at the start of a 35 mile ride then lunch after 22 ish miles. Seems like a lot of food to me.

imposter2.0

Either way, it's not bonk.

marcusjb

+1 on what imposter says - it isn't the bonk. You're not going to have run out of glycogen stores with the calories you've taken on board. Eat that flapjack a little earlier though maybe (or porridge, bit of fruit etc.). But you're not bonking (when and if you ever do, you'll know that it really is a horrible experience!).

Ride more and don't worry about people being amazed about having lunch on a 35 mile ride (what is the point of going on a bike ride if you can't stop at a cafe?). Ride that 35 mile route a few more times, you'll soon get past that feeling of nothing in the legs in the last part.

kajjal

Bonking is really severe power failure and will probably affect your balance as well. The last time I did it was ten miles from home when I ran out of food. I had to drag myself up a long hill much slower than normal.

jgsi

It doesnt have to be a severe reduction... overestimating my pacing on a recent 25TT, I basically went out the rear door after 22 miles, watts went down by 40 for those last 3 miles. After finishing, the legs would hardly turn over to get back to HQ... sods law it was uphill back to it as well.
HR came down also down by a margin as the muscles too fatigued to return power despite my cardio system having the ability to deliver. Just understimated fuelling priorhand and importantly giving enough time for any fuel to be fully in the system as well.
I do a 25 once in a blue moon 'cos they hurt so much.. you can do a 10 on 2 espressos to put it simplistically.

tozi1

Thanks for all the replies-more miles it is!

BLW

Sounds like lack of fitness (endurance) but most likely your eating pattern.

If you're eating the right foods, at the right times, you should have enough in the tank to do that distance if you are used to doing up to 20 miles regularly at a comfortable speed that suits you.

Are you drinking enough fluids both before, during and after?

kajjal

JGSI wrote:

It doesnt have to be a severe reduction... overestimating my pacing on a recent 25TT, I basically went out the rear door after 22 miles, watts went down by 40 for those last 3 miles. After finishing, the legs would hardly turn over to get back to HQ... sods law it was uphill back to it as well.
HR came down also down by a margin as the muscles too fatigued to return power despite my cardio system having the ability to deliver. Just understimated fuelling priorhand and importantly giving enough time for any fuel to be fully in the system as well.
I do a 25 once in a blue moon 'cos they hurt so much.. you can do a 10 on 2 espressos to put it simplistically.

It always happens with a big hill between yourself and home

tozi1

Think the fluids were ok to be honest-it was just the sudden onset of fatigue that threw me,that and the fact that a longish open water swim was no problem the day before.I think really it's just ride your bike,ride your bike,ride your bike!

team47b

Probably not a hypo as others have said, but if you eat hi GI fast acting processed food it is entirely possible to bonk AFTER eating, it is called post prandrial hypoglycemia, try to eat a combination of slow and fast acting carbohydrates when on the bike and protein and carbs within half an hour of getting off the bike to replenish glycogen stores, blood glucose can be affected up to 18 hours after exercise.

tozi1

Helpful advice Team47b.the trick seems to be to keep nibbling and sipping rather than binging.thanks.

pandazoo

May help ...http://tunedintocycling.com/2008/05/10/ ... -the-bonk/

tozi1

thanks pz.nice link.cheers.

okgo

It does happen sometimes that despite eating something sizeable like a meal, that your body does take about 20-30 mins to start turning it into energy. I had it the other month. 60 miles, stopped for lunch, sandwich and chips (pro diet!) and then set off and felt awful, really found it hard. Then about 30 mins later I was flying again.

secretsam

"The bonk" is like "The 'flu". Lots of people talk about having it but until you've really had it, you've no idea.

You literally can barely ride. Actually, the 'flu comparison isn't a bad one...your legs just go, every effort is exhausting. It's truly, really horrible.

iPete

Very eager a few years ago, armed with my mountain bike on slicks and a single bottle of water, I went on a 'long ride'.

About 4 miles from home, all power went but carried on before eventually coming to a dizzy halt less than half a mile from the front door, threw the bike down and just lay on the pavement until my recovered vehicle arrived. That was a proper bonk.

Covered a staggering 27 miles too

norvernrob

SecretSam wrote:

"The bonk" is like "The 'flu". Lots of people talk about having it but until you've really had it, you've no idea.

You literally can barely ride. Actually, the 'flu comparison isn't a bad one...your legs just go, every effort is exhausting. It's truly, really horrible.

I had no idea what it was until last week. I went on the turbo Friday evening, all I'd eaten all day was fruit and yoghurt for breakfast then a bar of chocolate around 2pm (I'm a postie and worked that day too).

I started off with some intervals then made the last 15 minutes a TT with as much power as I could put out. As soon as I got off the bike I didn't know if I was going to faint or be sick first. I had to sit on the floor, then managed to get in the shower and sat down in there, then had to lie down and pretty much couldn't get up for the next 10 minutes. It felt exactly like I'd got the flu.

I've been wrecked before, done some horrible turbo sessions but have never felt like that. It took around 20 minutes and some sweet food to come around. I then ordered a massive mixed kebab and wolfed the lot down

Kieran_Burns

Kajjal wrote:

JGSI wrote:

It doesnt have to be a severe reduction... overestimating my pacing on a recent 25TT, I basically went out the rear door after 22 miles, watts went down by 40 for those last 3 miles. After finishing, the legs would hardly turn over to get back to HQ... sods law it was uphill back to it as well.
HR came down also down by a margin as the muscles too fatigued to return power despite my cardio system having the ability to deliver. Just understimated fuelling priorhand and importantly giving enough time for any fuel to be fully in the system as well.
I do a 25 once in a blue moon 'cos they hurt so much.. you can do a 10 on 2 espressos to put it simplistically.

It always happens with a big hill between yourself and home

Fairer to say ANYTHING becomes a big hill when it hits. I was less than a mile from the car when I first experienced the joys of the bonk. There's this TINY incline, you can barely see it on any normal ride, I got to it and everything just... stopped, legs seemed to belong to someone else and my eyesight did that weird camera thing they sometimes bend your perception with in films. I don't clearly recall getting back to the car, I DO recall sitting leaning against the off-side rear wheel for a good 20-30 mins.

secretsam

Don't let the above stories of "the bonk" put you off cycling, mind :twisted:

Stuart.M

dont wanna jack the thread, but think ive experienced something similar. ive done 3 rides over 80 miles now, and on every one when i hit 50/60 miles my legs gave up, my pace slowed to 7/8 mph especially on hills and 12/13 on flat. then after 10-20 miles i got a second wind (and usually having to stop and eat). trouble is i dont feel exhausted, infact apart from 1 time ive felt like ive had the energy but just nothing in the legs. is this just a case of building up my stamina and endurance?

Kieran_Burns

It depends: are you actually eating and drinking before your legs give up and wave a little white flag? Or do you wait until this point before eating?

If it's the latter, then you're a pillock

You should aim to be eating small amounts at least every hour as you are not eating for 'now' but for in a couple of hours time.

The concept is simple enough:

You have a fuel tank (glycogen store)
As you cycle you start to empty the tank
If the tank goes empty you stop

So:
As you cycle and the tank is emptying, you add fuel (food) as you go. You can only add so much fuel at a time so you need to match your effort to the amount in the tank and how much you can add before the end of the ride.

The equation would look like:

Et = Es + Ei - (W x T)

Where:
Et - Energy Total
Es = Energy Start
Ei - Energy Intake
W = Watts
T = Time

the trick is keep Et above 0 by the end of the ride

thegreatdivide

SecretSam wrote:

"The bonk" is like "The 'flu". Lots of people talk about having it but until you've really had it, you've no idea.

You literally can barely ride. Actually, the 'flu comparison isn't a bad one...your legs just go, every effort is exhausting. It's truly, really horrible.

100% this. It's only happened to me once and I had to go to bed - and that was upstairs! Trully awful.

Stuart.M

Kieran_Burns wrote:

It depends: are you actually eating and drinking before your legs give up and wave a little white flag? Or do you wait until this point before eating?

If it's the latter, then you're a pillock

You should aim to be eating small amounts at least every hour as you are not eating for 'now' but for in a couple of hours time.

The concept is simple enough:

You have a fuel tank (glycogen store)
As you cycle you start to empty the tank
If the tank goes empty you stop

So:
As you cycle and the tank is emptying, you add fuel (food) as you go. You can only add so much fuel at a time so you need to match your effort to the amount in the tank and how much you can add before the end of the ride.

The equation would look like:

Et = Es + Ei - (W x T)

Where:
Et - Energy Total
Es = Energy Start
Ei - Energy Intake
W = Watts
T = Time

the trick is keep Et above 0 by the end of the ride

I do try to eat well before the ride, high carb dinner the night before a big ride, good breakfast (muesli or porridge and fruit) I take real food with me like flap jack, and some jelly babies plus I've got 2 750ml bottles I'll always pop a tab in.
I don't eat for the first hour then roughly every 20 mins. Like I say though, it feels like I have the energy just nothing in my legs to put the power down, but maybe I should try fueling earlier?

Kieran_Burns

Picture a graph:

Y axis is the energy left
X is time

The line will start going down the moment you start cycling, and will plateau / rise / flatten slightly as you take in energy. As you can only absorb so much over an hour, you need to temper your enthusiasm to your ability.

Otherwise it's just a matter of getting better

kajjal

thegreatdivide wrote:

SecretSam wrote:

"The bonk" is like "The 'flu". Lots of people talk about having it but until you've really had it, you've no idea.

You literally can barely ride. Actually, the 'flu comparison isn't a bad one...your legs just go, every effort is exhausting. It's truly, really horrible.

100% this. It's only happened to me once and I had to go to bed - and that was upstairs! Trully awful.

o

I have had it twice, once on road about seven miles from home and also when mountain biking we made the mistake of parking the car on top of a long hill climb. It is just brutal and worse than just getting hungry and losing a bit of power.

Jafaremraf

I am so glad I've read this thread as I think this is what has happened to my 12 year old on two occasions. The first was at the Tour de France in Harrogate when he had a go on a bike fixed to a roller in front of a screen and it was a race to get the fastest time. He finished and within 5 minutes the coloured drained from his face, he felt sick and had to lie down..... He fell asleep on the grass surrounding by hoards of people! Then it happened again a few weeks later after only cycling for 3 miles....we had stopped, I went in a shop and when I came out he was pale, said he couldn't see or hear properly and was very faint. He recovered fairly quickly. I was beginning to worry that something was wrong, until I worked out what his diet had been beforehand and I realised he was probably running on rubbish on those two occasions! And this thread has provided greater insight into what is likely to have happened.

Wrath Rob

Kajjal wrote:

thegreatdivide wrote:

SecretSam wrote:

"The bonk" is like "The 'flu". Lots of people talk about having it but until you've really had it, you've no idea.

You literally can barely ride. Actually, the 'flu comparison isn't a bad one...your legs just go, every effort is exhausting. It's truly, really horrible.

100% this. It's only happened to me once and I had to go to bed - and that was upstairs! Trully awful.

o

I have had it twice, once on road about seven miles from home and also when mountain biking we made the mistake of parking the car on top of a long hill climb. It is just brutal and worse than just getting hungry and losing a bit of power.

Nah, its great, just like being on drugs. Your legs go all wobbly, you float all over the place and you start hallucinating. Great fun, unless you happen to be piloting a wheeled vehicle at 15+mph on a public road. Oh, wait a minute....

As Sam says, you know when you've bonked. The OP is just comparatively unfit for the given distance and speed and has run out of endurance. I had it at the weekend too, after 3 hours my legs simply gave up and I had to cling on to the group for 30 mins before crawling the last 20 mins home by myself. Definitely not bonk as I was fuelled and watered after the cafe stop, just not fit enough.