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Running 50km after 82h of fasting

blog.xavivives.com

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Re: Running 50km after 82h of fasting

#91

Post by Bjartr »

brianwawok wrote: post #76
zimpenfish wrote: post #51

Earlier quoted context omitted.

> A slightly above average runner can do say 8 min miles over 26.2 miles on flats I make that a 3:30 marathon which I would suggest is rather more than "slightly above average" - you'd be in the first 25% male finishers at London 2015, for example.

I consider 25th - 40th percentiles as slightly above average... as many many of those people in your race are running their first and only marathon. Of people who do at least 1 marathon a year, I don't think you will find a 3:30 marathon much past the middlepoint. Not even close to an open BQ time for example.

While your intuition here may well be valid, to an outside observer it looks like you're cherry picking numbers without justification. Why 25th-40th percentiles? Do we know the distribution of first-and-only marathon runners to repeat runners or is this a pure intuition? If the latter I would be concerned about the flaws that exist in human thinking when it comes to generalizing over groups.

Re: Running 50km after 82h of fasting

#92

Post by pc86 »

brianwawok wrote: post #74
pc86 wrote: post #67

Earlier quoted context omitted.

> A slightly above average runner can do say 8 min miles over 26.2 miles on flats What is it about the running community that makes them say ridiculous things like this? The fastest average marathon pace I could find anywhere was 9m 6s for 20-year old men.[0] To say that it takes only someone "slightly" above average to maintain a pace 12% faster than that for an entire marathon is ridiculous. Just because a lot of p…

That site seems pretty bogus. Lets pick a real race. Say the 2015 Chicago Marathon. Let's look at men 30-34 http://results.chicagomarathon.com/2015/?pid=list 3200 people there finished. So let's take middle, #1600: 4:11, which is 9:34 pace. 8 min pace is 3:29, which is something like finish 700 / 3200 in that age group. So to me, finishing in 700th place out of 3400 people in a race is "slightly above average". But w…

> That site seems pretty bogus.

I agree, my point was that the fastest "average" time I could find (regardless of quality of the source) was still sufficiently slow enough compared to the 8:00 pace figure that 8:00 is in fact not slightly above average.

Re: Running 50km after 82h of fasting

#93

Post by OldSchoolJohnny »

xavivives wrote: post #59

I did not see a doctor. Not before, not after. The truth is that even if I had seen one I wouldn't take in account her opinion anyway. The current standards for nutrition are based on a diet rich in carbohydrates. Any response from a doctor (at least the ones I have access to) will discourage this event. It just doesn't fit on their models. Plus they have to play safe. I appreciate all the people who are concern abou…

Personally I've come around to your point of view. Every week I play a very intense sport consisting of a lot of quick short sprints back and forth for hours and I've self experimented with going the full carb loading route and also the full ketosis for weeks route and repeated a few times over the years. When I play after the low almost no carb eating way I have far more stamina, much greater than people half my age who are playing with me. However I also find it takes a bit longer to warm up and get my wind under low carb but only by a few minutes.

I highly encourage anyone to try this out for themselves the difference can be startling.

Re: Running 50km after 82h of fasting

#94

Post by MichaelRenor »

I'd like to add my own data points for low-carb/ketosis and exercise. In the beginning it was very hard and I felt extremely lethargic (typically 3 to 4 days after switching to The worse I ever felt was during that time (3-4 days in). After that I would slowly improve and within a few weeks could almost reach my normal max, though never exceeded them. The bonus part was that I was melting off pounds of fat.

This was just my experience. I found that salty drinks (such as chicken stock) helped a lot when first beginning low carb to prevent the lethargic feeling ~3 days in.

Re: Running 50km after 82h of fasting

#95

Post by IgorPartola »

zimpenfish wrote: post #55
brianwawok wrote: post #44

Earlier quoted context omitted.

I think you are conflating two things. Losing weight you do outside of races. Eat less, exercise more - you lose weight. Now during an actual race - do you want to burn sugar or fat? Your body has a TON more fat, even a skinny guy has 50k calories of fat he can burn.. whereas the same guy only has 2k calories of sugar to burn. However burning fat is less efficient, so you are unlikely to set a speed record doing it.…

You can, perhaps, train yourself to burn fat more efficiently which helps. e.g. http://home.trainingpeaks.com/blog/article/using-low-carbohy...

Cool. Though your linked article still states that peak fat burn output is still lower than peak carb burn output and that high intensity still is best served by carb rich diet.

Re: Running 50km after 82h of fasting

#96

Post by IgorPartola »

brianwawok wrote: post #69
IgorPartola wrote: post #50

Earlier quoted context omitted.

OK that makes sense. So then what's the point of doing the fasting + racing thing? Seems like it'll just be very slow and difficult for you to do it.

Well in theory you run out of sugar calories after 2000 calories, but you have 50-100k fat calories. If he trains a lot in a fasted state, in theory he would have a much larger bank of energy to draw from. Many animals, for example dogs, mostly burn fat. On the other hand, burning fat is less effecient, so your peak output is lower.

That makes sense. So basically as long as you don't run more than 20 miles or equivalent, the benefit of low carb training is less noticeable.

One more question: what about proteins as a fuel source?

Re: Running 50km after 82h of fasting

#97

Post by brianwawok »

IgorPartola wrote: post #96
brianwawok wrote: post #69

Earlier quoted context omitted.

Well in theory you run out of sugar calories after 2000 calories, but you have 50-100k fat calories. If he trains a lot in a fasted state, in theory he would have a much larger bank of energy to draw from. Many animals, for example dogs, mostly burn fat. On the other hand, burning fat is less effecient, so your peak output is lower.

That makes sense. So basically as long as you don't run more than 20 miles or equivalent, the benefit of low carb training is less noticeable. One more question: what about proteins as a fuel source?

So taking a step back, as you go about a day you are always getting some energy from sugar stores, and some from fat stores. Example graph:

http://www.sportsscientists.com/wp-content/uploads/2010/01/F...

Sitting still mostly fat. Normal person as you work harder, more and more come form sugar stores - as it can get you energy faster.

All this is separate from calories you are taking in. You could eat sugar (sports drink), fat (an avocado), or protein (bacon) while you exercise. Your body will turn all of these into "sugar" which will then fuel your muscles through sugar. Fat is the longer term storage mechanism in the body. So while you could fuel a race by eating avocados or bacon, most people would have stomach issues.. as your stomach starts to shut down the harder you work (blood is in muscles not in gut, etc.). So this why when we talk about fueling in a race fat vs sugar, it's not really related to the source we are taking in our calories from.

Re: Running 50km after 82h of fasting

#98

Post by merpnderp »

I know the 4 months I went on low/no carbs, I had never felt better, had more energy, or lost weight faster. I lost 43lbs, saw my cholesterol and triglycerides go from marginal to perfect, and ate as much as I wanted.

Course then my gallbladder stopped pumping and I haven't tried it again, although I don't see why I couldn't.

Re: Running 50km after 82h of fasting

#99

Post by brianwawok »

Bjartr wrote: post #91
brianwawok wrote: post #76

Earlier quoted context omitted.

I consider 25th - 40th percentiles as slightly above average... as many many of those people in your race are running their first and only marathon. Of people who do at least 1 marathon a year, I don't think you will find a 3:30 marathon much past the middlepoint. Not even close to an open BQ time for example.

While your intuition here may well be valid, to an outside observer it looks like you're cherry picking numbers without justification. Why 25th-40th percentiles? Do we know the distribution of first-and-only marathon runners to repeat runners or is this a pure intuition? If the latter I would be concerned about the flaws that exist in human thinking when it comes to generalizing over groups.

> Why 25th-40th percentiles

Why not? Someone wanted to quantify "slightly faster than average", so I made up some percentiles. I don't think there is a scientific definition of "slightly faster than average" so I think I can do this. You could I suppose counter with you think it means "35th-49th percentiles" which is valid but doesn't really change the argument too much.

> Do we know the distribution of first-and-only marathon runners to repeat runners or is this a pure intuition?

Just intuition. It would be a tricky thing to survey, as you would need to wait for all current people who have ran exactly 1 marathon to die, to confirm they do not indeed run more .

Re: Running 50km after 82h of fasting

#100

Post by dang »

ygjb-dupe wrote: post #43
powera wrote: post #21

Could all the people without medical knowledge please stop saying that their lack-of-medical-knowledge make them smarter than the guy that actually did this? Your requests for various random chemical levels are stupid. We have done science for thousands of years before blood tests were invented.

Yeah, we did science for thousands of years, but medical science has had (and still has) to contend with pseudo science and snake oil continuously (for a modern take, see homeopathy). An anecdote about a personal experience in relation to an exercise and diet regime doesn't make a person smart, and asking questions about the experience doesn't denigrate the author of the anecdote. Weight loss and nutrition are the bo…

> Weight loss and nutrition are the bogey man of the health industry

They've become a bogeyman of internet forums too. Throw in weight lifting for the trifecta.

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