Is it possible to feel "bonked" even when you've consumed enough food?

[Andrew21]

So my question is can one feel "bonked" even when they've consumed enough food? In other words, can you push yourself so hard that your body shuts down to the point you can hardly turn the pedals?

I'm asking because I raced yesterday for the first time this season, and it was hard, I got dropped, but finished even though I was absolutely spent. After the race, there was about a 3km ride back to the car that took me probably 15 - 20 minutes, I was essentially at a standstill going up even a small incline, and all the other racers were zooming past me.

I won't post what I ate during the race, because instead of having my question asked I'm going to start having my race nutrition analyzed. Pretend I ate the maximum amount of processable calories - could I still have felt the way I did? Or to be that trashed after a race would it have to have been a lack of food energy?

Thanks!

 

[jhuskey]

Food is only part of the equation. The bodies ability to move fuel and O2 to the muscles is another part of it. The answer is yes it is very possible.

 

[polkadot]

Yes it's definitely possible to feel bonked even though you've eaten for Britain! It's usually when you have pushed yourself really hard and been well over threshold for quite a bit of the race or ride. Your body sometimes almost shuts down and doesn't absorb the calories you are consuming fast enough. Some people also get a 'sugar' high and then a low afterwards, particularly with gels and are therefore better eating bars.

 

[Andrew21]

Ok thanks that's good to know! The race time was only around 2:15 and I still ate a fair amount for me, so I'm glad there could be other causes (or else I'd be packing a backpack of food for future races). It's hard to imagine eating much more. Also it was the first hot day of the year here which definitely contributed!

 

[alienator]

Ok thanks that's good to know! The race time was only around 2:15 and I still ate a fair amount for me, so I'm glad there could be other causes (or else I'd be packing a backpack of food for future races). It's hard to imagine eating much more. Also it was the first hot day of the year here which definitely contributed!

You might be better off rethinking what you ate before and when you ate before the race. Likewise you should rethink what and when you ate during the race.

 

[maydog]

I have seen several reliable sources indicate that your body can process about 300 calories an hour from food intake. During hard riding, you consumption is much more than that - even at a moderate intensity over (a lot of) time, I suspect that most anyone will bonk.

I do not have the sources handy, but have seen data that at a fixed power output the body gradually shifts from a glycogen burn to a fat regardless of carbohydrate intake. Carb intake can slow the process and it usually occurs over several hours.

 

[digibud]

You get very little energy from food you ate an hour ago unless it is sugar. Even complex carbs take a while to be digested and available. The breakfast you ate at 8AM is of little or no use to you at 10AM. You can forget meat and cheese (proteins and fats) entirely if you ate them an hour or two ago. The first hour or two you are burning stored glycogen in your muscles and it is being replaced by food you ate many hours ago. Energy drinks with carbs and some sugar will get you some replacement. For a one or two hour race, the key is carbo loading the night before with some energy drinks during the day. Good hydration is also critical. People smarter than me should chime in and correct me. I'm no expert and this ain't gospel.

 

[danfoz]

Originally Posted by digibud .

You get very little energy from food you ate an hour ago unless it is sugar. Even complex carbs take a while to be digested and available. The breakfast you ate at 8AM is of little or no use to you at 10AM. You can forget meat and cheese (proteins and fats) entirely if you ate them an hour or two ago. The first hour or two you are burning stored glycogen in your muscles and it is being replaced by food you ate many hours ago. Energy drinks with carbs and some sugar will get you some replacement. For a one or two hour race, the key is carbo loading the night before with some energy drinks during the day. Good hydration is also critical. People smarter than me should chime in and correct me. I'm no expert and this ain't gospel.

Good point. However the breakfast one ate at 8am is of great use to the body by 11 and 12. The stomach contents of a well hydrated person will start their course through the small intestines, where most nutrients, fats and proteins are absorbed, around three hours after being consumed (longer in someone dehydrated). Carbs will start being digested via salivary amylase the second one starts chewing the food, and blood sugar levels will respond accordingly. Try sucking and chewing on a slice of Wonder - with almost zero fiber, one can quite literally get it to melt in the mouth, with almost nothing left over to swallow. It's for this reason that after a couple hours at threshold one can bonk to the point of not even being able to turn over a granny gear, but within 10-15 minutes of consuming simple carbs like a can of coke or a candy bar, get enough in the tank to ridel the last 10 miles home. This last observation is from my own experience.

It's not very important to eat immediately prior a 1 or 2 hour race, but it is important for longer races/events to start eating soon after the start so that food is being broken down for glucose to be used used in hours 3, 4, and 5 (if the event runs that long).

 

[swampy1970]

It's most likely a combination of not eating enough and having to ride harder than expected. The former leading to a situation where your glycogen stores are depleted and the later forcing you to become glycogen depleted during a ride. Better planning can solve the eating situation - make sure that in the days preceding the race you're eating enough, especially within an hour of your training sessions, unless it's not an important race and you're trying to lose weight via calorie restriction and/or extra training. Make sure that you eat a couple of hours before the ride too and if you have a good warm up before the ride get something down your neck after that.

As you become fitter/faster your utilization of fat and glycogen for a given effort will change. If your threshold gives you around 24mph on the flat now and in a year you can do 26 then the utilization of fat as a fuel will be a little different at 24mph a year down the road. Likewise, you can somewhat train your body to be more comfortable with consuming more food on the bike under effort - but the key is that if you're having problems with 2 hour events then either you need to train a lot for 2+ hours and eat accordingly or you need to enter a lot of 2 hour events that you'll need to eat in... Just like with regular training, you need to do it in order to get better at it.

 

[JSWin]

Oh this is a good one. It still has to do with what you ate. I guarantee you were not carbed up. If you had anywhere between 10-20 bananas and some kind of potatoes or rice the night before this would not happen. The fruit will make you like a superhero. You are definitely cutting yourself short if this happened.