The bonk - when you least expect it

[Garry Booth]

If I eat anything sweet around lunchtime onwards I can almost guarantee that I will bonk horribly on the ride from work to home at around 5:30. That's without riding hard and after only maybe 1 or 2 miles. In fact, I have found that I sometimes bonk around that time before getting on my bike if I have had something sweet earlier!
Weirdly, in other circs, I never bonk. Even after a day in the saddle say on a sportive or audax.
Anyone else have this experience?

[nez]

See your gp and ask for a diabetes test. You fast and then drink glucose and they measure your blood sugar before and after.

[Vantage]

In fact, I have found that I sometimes bonk around that time before getting on my bike if I have had something sweet earlier!

Define 'sweet'.
'sugary' foods tend to burn off fast compared to what I would call wholesome foods. It can cause a rubber band effect in your glucose levels. They can shoot up and then bounce back to a lower level than they were originally leaving you feeling weak or tired.
This can affect anyone, not just diabetics.
See if the same thing happens after eating sandwiches or something. If not, no need for a diabetes test.
I'm speaking as a type 1 diabetic for 35 years.

[Mick F]

Sounds to me that you're not eating enough.

Good breakfast before riding to work, and a good lunch. You shouldn't need anything sweet.
Eat a good meal in the early evening.

[NATURAL ANKLING]

Hi,
If not eating a sweet something what would you eat at that time
http://eatingisthehardpart.com/2011/07/ ... y-schleck/

The only thing I am (never have) not eating is the gels...............

[Garry Booth]

It's interesting because I do eat plenty at breakfast and lunch. It only happens if I eat say a slice of very sweet cake or eg a Mars bar as well. In other words if I avoid that kind of snack around midday all is fine.
Just find it interesting that it happens. G

[AJ101]

If you drop the carbs and move to a higher protein / fat based diet you'll start to become more fat adapted. Bonking in a non racing situation will happen a lot lot less, your energy levels will also become more consistent throughout the day.

edit: for every sugar spike you have, from a mars bar or cake, you'll experience a corresponding slump an hour or two afterwards.

[Mick F]

+1
Absolutely!

[mjr]

I read that free sugars (basically, not bound into fruits or whatever) confuse some people's appetite, so you won't eat enough other stuff, or you might eat too much. Other people suffer sugar crashes a while after eating refined sugars. It's surprisingly not very well understood.

[NATURAL ANKLING]

Hi,

If you drop the carbs and move to a higher protein / fat based diet you'll start to become more fat adapted. Bonking in a non racing situation will happen a lot lot less, your energy levels will also become more consistent throughout the day.

Not sure what you are trying to say here, this goes against everything we know and I have practiced all my life.
https://www.findingbalance.com/articles ... out-carbs/
"Your energy level will drop without enough carbs.
Our bodies store a limited supply of carbohydrates in the form of glycogen–in both the muscles, and liver. We draw on the muscle glycogen and some of our stored fat for daily energy, especially with exercise or physical labor. Fat can’t be used as the exclusive fuel, so when the carbohydrate reserve is depleted, we feel very fatigued."

"Carbohydrates affect your moods.
Carbohydrates help keep up the levels of serotonin in our brains. Serotonin is a chemical that produces a feeling of calm, improved mood and reduced appetite. Some people are especially sensitive to serotonin levels, so when they cut back on carbohydrates and their levels drop, they start to feel depressed or worsen their existing depression. Others find themselves feeling nervous, short-tempered and/or moody.

On the other hand, if you binge on a lot of high carbohydrate foods at one sitting, sluggishness and grogginess can result. It’s best to eat moderate amounts of carbohydrates throughout the day, to maintain even moods and keep energy levels up.
"

edit: for every sugar spike you have, from a mars bar or cake, you'll experience a corresponding slump an hour or two afterwards.

No problem there......
"Eating too many high-glycemic foods may increase health risks.
These foods are quickly digested and flood your bloodstream with a lot of sugar all at once. The pancreas in turn releases a large amount of insulin to clear the blood stream of the excessive sugar. The problem is, there is a rebound effect, tipping blood sugar levels back to the low side. When your blood sugar level drops too low soon after a meal, you’re going to get hungry again and are apt to overeat."

If you need more energy just eat more of the same...........we all suffer from the odd craving

[Garry Booth]

Interesting discussion. Thanks people. Hitting the Black Mountains this weekend. Let's see what that does to the bonk dial...

[Mick F]

Cycled over Gospel Pass some years ago. June 2006.
Damned cold up there! My fingers were blue whilst descending through Llanthony.

Bonk? Forget it!
Just keep warm!
June was bad enough, but December is awful up there.

[AJ101]

Hi,

If you drop the carbs and move to a higher protein / fat based diet you'll start to become more fat adapted. Bonking in a non racing situation will happen a lot lot less, your energy levels will also become more consistent throughout the day.

Not sure what you are trying to say here, this goes against everything we know and I have practiced all my life.
https://www.findingbalance.com/articles ... out-carbs/
"Your energy level will drop without enough carbs.
Our bodies store a limited supply of carbohydrates in the form of glycogen–in both the muscles, and liver. We draw on the muscle glycogen and some of our stored fat for daily energy, especially with exercise or physical labor. Fat can’t be used as the exclusive fuel, so when the carbohydrate reserve is depleted, we feel very fatigued."

"Carbohydrates affect your moods.
Carbohydrates help keep up the levels of serotonin in our brains. Serotonin is a chemical that produces a feeling of calm, improved mood and reduced appetite. Some people are especially sensitive to serotonin levels, so when they cut back on carbohydrates and their levels drop, they start to feel depressed or worsen their existing depression. Others find themselves feeling nervous, short-tempered and/or moody.

On the other hand, if you binge on a lot of high carbohydrate foods at one sitting, sluggishness and grogginess can result. It’s best to eat moderate amounts of carbohydrates throughout the day, to maintain even moods and keep energy levels up.
"

edit: for every sugar spike you have, from a mars bar or cake, you'll experience a corresponding slump an hour or two afterwards.

No problem there......
"Eating too many high-glycemic foods may increase health risks.
These foods are quickly digested and flood your bloodstream with a lot of sugar all at once. The pancreas in turn releases a large amount of insulin to clear the blood stream of the excessive sugar. The problem is, there is a rebound effect, tipping blood sugar levels back to the low side. When your blood sugar level drops too low soon after a meal, you’re going to get hungry again and are apt to overeat."

If you need more energy just eat more of the same...........we all suffer from the odd craving

Sorry mate, while there's a lot of practical day to day advice in that article, there's also a lot that isn't.

Honest question - when did you make the decision to go on a high carb diet?

[NATURAL ANKLING]

Hi,
I never said "high" anything I am in the "balanced" camp.

I eat white rice because brown takes longer to cook, forever even.
But I would like to change to a better diet so I will put my thinking cap on
I might substitute white rice with pasta some of the time.