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The dreaded bonk!

Jordan93Jordan93 Posts: 336
edited October 2010 in Health, fitness & training
Was out doing my usual 30 mile ride when with around 8 miles to go I started to bonk, at some points I was struggling to hold 8mph on the flats. I drank around 2.5L while I was out too. How much and how often do you guys eat?

Posts

  • Whats bonk?!
  • Jordan93Jordan93 Posts: 336
    Google it :lol: , im more of a roadie so maybe you lot don't know what a 'bonk' is
  • mobilekatmobilekat Posts: 245
    There were some interesting results to googling Bonk......

    But the repeatable version (and thus the one I guess you mean) appears to be 'hitting the wall'

    We tend to have a decent cooked breakfast, then head out, we normally consume a couple of muesli bars, 750mls Zip-vit energy drink, a bag of energy chews and about 2 litres of sugar free squash in a 3-5 hour ride.

    With the odd bananana thrown in, or ice-cream if we pass a van (bless Dartmoor)

    That keeps us well fueled up. and stops the nasty dehydrated headache!
    Wheeze..... Gasp..... Ruddy hills.......
  • Jordan93Jordan93 Posts: 336
    mobilekat wrote:
    There were some interesting results to googling Bonk......

    But the repeatable version (and thus the one I guess you mean) appears to be 'hitting the wall'

    We tend to have a decent cooked breakfast, then head out, we normally consume a couple of muesli bars, 750mls Zip-vit energy drink, a bag of energy chews and about 2 litres of sugar free squash in a 3-5 hour ride.

    With the odd bananana thrown in, or ice-cream if we pass a van (bless Dartmoor)

    That keeps us well fueled up. and stops the nasty dehydrated headache!
    Yes, the repeatable version is what I meant! I had a decent breakfast but I guess i misjudged my food intake. In future I'll take enough and some to make sure if I do bonk then i'll make it home rather than weaving at 8mph home :lol:
  • I've found that I have to bring a nice fat sandwich with me in the bag to munch when I get myself to the top of the climbs, otherwise I just die on the downhill parts.

    I suggest energy bars and a sandwich should be tucked away in the bag to help out.
  • ollie51ollie51 Posts: 517
    Bonking really isn't nice; try 1g of carbs, per KG of body weight, per hour for moderate intensity exercise. As a general rule stick to that :)
  • Take some glucose tablets with you as well. If you "hit the wall", pull over, have 3-4 tablets with a drink - 5 minutes later have a cereal/energy bar and set yourself off again.

    What is happening is that you have having what diabetics call a Hypo, this is when you blood sugar level drops too low. The glucose tablet will give you a quick boost with the bar giving you some slower release carbs.
  • Being diabetic I find it hard to find decent hi energy foods/drinks to take along as they tend to contain glucose and other sugar derivatives for fast energy replenishment.

    A bag of peanuts or sesame seeds tend to be a low GI and slow energy release throughout the ride. This is also a good idea for non-diabetics to take with as its a more balanced energy release.
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  • weeksy59weeksy59 Posts: 2,606
    TO be honest if you ask me, you shouldn't require ANYTHING for a 30 mile ride apart from water it's 30 miles not 300.
  • weeksy59 wrote:
    TO be honest if you ask me, you shouldn't require ANYTHING for a 30 mile ride apart from water it's 30 miles not 300.
    Saying you should not need anything at all is ridiculous. Everyones fitness levels are different. 30 miles to some is quite a distance.
  • weeksy59weeksy59 Posts: 2,606
    it's his 'usual' ride, so you'd assume his fittness is respectable. Based upon that although it may be a desire to eat,or even 'nice'... you shouldn't be reaching failure really without eating.
  • Remember though fitness levels are different and although it is his usual loop there are several factors that can influence exhaustion levels. He may have been riding 4 times a week, but only for a month so will not be the same fitness level of someone who has been riding that loop for years. Weight, weather, altitude, oxygen levels, any health complications, food within the past day as well as many other factors influence it.
  • weeksy59 wrote:
    TO be honest if you ask me, you shouldn't require ANYTHING for a 30 mile ride apart from water it's 30 miles not 300.

    It all depends how long the ride takes.

    30 miles on the road takes me around 2 hours, so I'll be happy with one bar and a couple of litres.

    Off road with big climbs and technical sections can take 4 hours, maybe more. Anybody would need food for that.

    My rule of thumb is one cereal or energy bar and one litre per hour, plus a handful of jelly babies and maybe a banana too just in case. It's by no means scientific, but I get by OK with it.
  • BriggoBriggo Posts: 3,537
    ollie51 wrote:
    Bonking really isn't nice; try 1g of carbs, per KG of body weight, per hour for moderate intensity exercise. As a general rule stick to that :)

    1g of carbs per KG per hour?

    You'd be a fat bast*rd if you did, the calorie intake would be huge surely and I definately dont need 70g's of carbs an hour to keep moving.
  • bails87bails87 Posts: 12,998
    steponahen wrote:
    weeksy59 wrote:
    TO be honest if you ask me, you shouldn't require ANYTHING for a 30 mile ride apart from water it's 30 miles not 300.

    It all depends how long the ride takes.

    30 miles on the road takes me around 2 hours, so I'll be happy with one bar and a couple of litres.

    Off road with big climbs and technical sections can take 4 hours, maybe more. Anybody would need food for that.

    +1

    I reckon 30 miles is a fairly big deal off road for most riders.

    But I'll happily do 20 miles on the road bike with just a bottle of water and a cereal bar in my pocket.
    MTB/CX

    "As I said last time, it won't happen again."
  • How does bonk feel? I've been getting this thing were I'll suddenly get a sore head during a ride, if I take a break it'll clear but as soon as I exert myself it'll come back. Also when I have it I find it harder to focus, which is a nightmare on technical descents as you can probably imagine.

    Sound like "bonk" to you guys? This year I've been stopping less and less as my skills get better so I don't get as many "natural breaks" in my riding and seem to drink less too.
  • Mickey Eye wrote:
    How does bonk feel? I've been getting this thing were I'll suddenly get a sore head during a ride, if I take a break it'll clear but as soon as I exert myself it'll come back. Also when I have it I find it harder to focus, which is a nightmare on technical descents as you can probably imagine.

    Sound like "bonk" to you guys? This year I've been stopping less and less as my skills get better so I don't get as many "natural breaks" in my riding and seem to drink less too.

    Bonk is lack of energy, sounds like what you are experience is dehydration headaches.
  • That could well be possible, how do you remember to drink? Because to be honest I never really feel thirsty.
  • Headaches could be related to vasodilation of the blood vessels in the head with a large amount of exertion. They pass over time as fitness increases.
  • Mickey Eye wrote:
    That could well be possible, how do you remember to drink? Because to be honest I never really feel thirsty.

    A general rule of thumb is 100ml per 15 minutes of exercise, and I normally try to stick to about that. But then again I could drink 100liters of water a day and still be thirsty, somehow i'm always thirsty. It may be something you need to just train yourself to do in order to keep hydrated.
  • ollie51ollie51 Posts: 517
    Briggo wrote:
    ollie51 wrote:
    Bonking really isn't nice; try 1g of carbs, per KG of body weight, per hour for moderate intensity exercise. As a general rule stick to that :)

    1g of carbs per KG per hour?

    You'd be a fat bast*rd if you did, the calorie intake would be huge surely and I definitely dont need 70g's of carbs an hour to keep moving.

    That's advice I've been told by sports scientists/doctors etc and I've stuck to it ever since I bonked properly (to the extent I couldn't speak or stand up). And the body fat content is 3.9% certainly not a "fat basta=*rd"
  • mr boosmr boos Posts: 40
    So if myself and mrs boos skip lunch will we bonk together later.............
  • Buckled_RimsBuckled_Rims Posts: 1,648
    weeksy59 wrote:
    TO be honest if you ask me, you shouldn't require ANYTHING for a 30 mile ride apart from water it's 30 miles not 300.

    +1 I agree.

    The OP says he's a roadie, a 30 mile training route even in a hilly area is not enough to bonk a body unless there's some serious underlying health problem or he's going at 100% for the entire time (even pros can't do that). A quick calculation shows if he averages 15 mph, that's 2 hours on the bike, which equals at about 1200 to 1600 calories burnt for a hard ride. Not enough for a bonk IMHO.

    As some have suggested, the OP hasn't drunk enough water and is confusing the effects of dehydration with a bonk.
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  • mr boosmr boos Posts: 40
    mr boos wrote:
    So if myself and mrs boos skip lunch will we bonk together later.............
    well we skipped lunch, and didnt bonk! I must be fitter than I thought
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