Carb Deplete and Load

I put together the background information on this question in my blog - for reference.

http://kayry-john.blogspot.com/2008/02/taper-recovery-trends.html

[quote]kayry wrote:

Where did you get the info on how to apply the Carb depletion. I have wanted to try it. But I couldnt find a lot of info on it.

Is it as simple as no carbs for a week and then lots of carbs for a few days?

thanks

I had not info on how - just saw posted by a 2:41 marathoner that he always depleted for 10 days than loaded for 3 so I just infurred the rest.

For the 10 days - I basically just tried to minimize carbs - bought some muscle milk to stock for quick breakfast and occasional snack, ate a lot of bacon wrapped beef or fish I bought at Sam's club. Eggs, skipped the buns on my fast-food burgers. Nuts - I liked peanut butter on a spoon for a snack :-).

For the 3 days - same in reverse - minimum protein or fat - so baggles, pasta, etc.

Anyway - since it was so successful I'm kinda on the hunt for information on how I was supposed to do it because the results were way beyond my expectations so I want to be sure I do it right next time.

Wow, 10-day depletion seems pretty extreme. I've did a much shorter version - maybe 2.5 to 3 days, but with a fair amount of running and a little bit of intensity to really drain the tank. Then I loaded immediately for about 3 days and ran just enough to stay loose.

Did it work? Well, it was the one and only marathon out of eight that I did not suffer a significant slowdown the last 6 miles. They were not easy, my legs were ready to give out, but I did not suffer that horrible drop off of mental and physical energy. But I'll also say that I also trained better for this one than for any of the others, too, so that certainly played a role as well.

Carbs are broken down into glycogen. Glycogen is stored in the muscles for fuel. When you don't eat carbs the muscles don't get the glycogen they need. When you start eating them agian the body stores as much glycogen as it can to compensate for going long periods of time without it. I read somewhere that after being depleated then loading the muscles can hold as much as 3 or 4 time the glycogen they normally carry.

Slow and Steady wrote:

Carbs are broken down into glycogen. Glycogen is stored in the muscles for fuel. When you don't eat carbs the muscles don't get the glycogen they need. When you start eating them agian the body stores as much glycogen as it can to compensate for going long periods of time without it. I read somewhere that after being depleated then loading the muscles can hold as much as 3 or 4 time the glycogen they normally carry.

So this clearly explains the ability to run longer - but what I can't figure is why FASTER - does that extra glycogen packed in there make it quicker/more efficient to translate to useable energy maybe - cut down on the fat use in favor of the more efficient fuel?

Adrenaline.

Slow and Steady wrote:

Adrenaline.

Yeah - I thought of things like that or reduced fatigue from taper or many other factors or the favorate catch-all answer people put when they don't know (improvement rarely happens in a straight line) - but what doesn't fit is I've had that in all prior marathons too and ran them all by heartrate too and this is the only one where there was a step change performance relative to my training - something was different in this race - and it quickly went away after the race too - the speed is not there 3 weeks later and I suspect will not be back in any race or training run without this deplete/load thing behind it. I don't buy "adrenaline".

I know you are looking for answers but I have more questions. Hopefully you wont mind.

I am running a fall marathon. I would like to use carb depletion for that but I want to try it first in another race. Just to see how it affects me. Do you think it would have any benefit in a half marathon?

Also do you think that the 10 days was excessive or the right amount for the depletion period?

toots

as the benefit saw was increased speed as well as endurance - I would think the increase speed would translate to all distances so certainly it would help for the 1/2 marathon.

Regarding the 10 day. Without knowing WHY it worked I cannot comment on if too long or even short. My thinking going in was it was basically an Atkin's diet and the longer I did it the more weight loss and the less weight to carry the distance - the faster - by that thinking the longer the better. If the benefit is just in loading up the muscles with glycogen - than I'd say I was fully depleted by day 6-7 (including running 50-60 miles within that period - some quality mileage included) and the extra days did little in the way additional depletion. If the benefit is somehow that the body's responce to the depletion is to generate red-bloodcells or in some other way improve oxygen delivery - than the more of those the better. So - a long way of saying - I don't know.

But I really like the idea of others giving it a try and reporting back how it went - so by no means is your question a bother as I'm very interested in how it goes for you - the experiences of many will likley yield better information than the experiences of one.

Any other input out there? Thanks. John

Let me try to offer my simple understanding, presented in a simplified way. Someone can quibble that I've neglected some details if they like.

You have a limited supply of glycogen (stored broken down carbohydrate) in your leg muscles. Glycogen is one source of fuel for running at marathon pace. The other primary source of fuel is fat.

Glycogen is a much more efficient fuel for delivering energy to the legs than fat at faster paces. When you run out of glycogen, you have only fat left to burn. At this point, you can no longer maintain faster running paces (like M-pace), and you "hit the wall."

The ratio at which you burn glycogen:fat depends on your pace. The faster you go, the higher the glycogen:fat ratio. Therefore the time/distance you can run is limited by the pace you are running. If you run faster than your actual marathon fitness, you will run out of fuel (glycogen) early and hit the wall. If you run slower than actual fitness, you won't run out of fuel before the finish line and will probably have managed negative splits. If you nail your optimum pace for the whole race, you are theoretically hitting the wall just as you cross the finish line.

The rate at which you burn glycogen:fat can be adjusted/improved through training. The amount of gas you have in the tank (glycogen stored in the legs) can be increased a little bit in a couple of ways: not wasting energy with a vigourous warmup before the marathon; taking in fuel during the race; and, optimal fuelling prior to the race.

Some people believe that the depletion/reloading technique allows a temporary increase in glycogen storage, so that you can arrive at the line with more fuel than you normally have on a day to day basis. I don't understand the physiology behind this effect, but personally I believe it to be true.

Anyhow, that's what I know. Or think I know.

Pete wrote:

Glycogen is a much more efficient fuel for delivering energy to the legs than fat at faster paces. When you run out of glycogen, you have only fat left to burn. At this point, you can no longer maintain faster running paces (like M-pace), and you "hit the wall."

I'm starting to think this is the key to it all - combined with

Slow and Steady wrote:I read somewhere that after being depleated then loading the muscles can hold as much as 3 or 4 time the glycogen they normally carry.

Would suggest by creating an abundance of glycogen stores in the body - the more efficient fuel - the body burns less fat and requires less oxygen for same power output which enables greater speed for same effort. Best theory I've heard - makes sense to me.

Thanks!

How do you know that if you had no depleted that you would not have run faster? A dilemma isn't it?

Depletion was common in the 60s and 70s based on research done at the time showing an improvement in muscle glycogen storage. However, Sherman came along and had runners not deplete and then eat a high carb diet in the days leading into training and combined with a taper, they did just as well in terms of muscle glycogen storage. That slowed the depletion craze although I have seen that runners use it from time to time.

The depletion was a combination of decrease carb intake and either very long runs or high intensity runs to "burn off" muscle glycogen.

Potential downsides to depletion:

1) Irritable runner syndrome: without carbs, the mood of the person just sucks.

2) Poor workouts during that period. Low quality work during a taper where some high quality work is recommended.

3) Doing something untried before a big race--this obviously varies.

From the graph above - for the marathon I ran most miles either at 162 bpm(87%max)/5:50-6:05 mpm or at 157 bpm(84%max)/6:05-6:15 mpm. The very best training runs I ever had prior (pink line) showed for that pace my heartrate should have been 168 or 165 bpm.

Put another way - in the course of 2 weeks - my Tempo pace (~5:55-6:00 mpm) became my Marathon pace. And then post race (after 3 weeks) it has gone back again to being my Tempo pace.

I did not see this happen at New York Marathon, I did not see this happen at Boston Marathon - both of which I did only the 3 day carb load - only in this marathon where I did a 10 day deplete followed by the same 3 day load.

So anyway - the data to me is quite pursuasive although I'll admit it is not all toghether convincing to me until I can repeat it.

I've most definately have read this in many books - and actually I went into doing it thinking only about the benefits of reducing the weight at the start-line thinking 1 lb usually means about 1 minute faster time as the depletion is essentially the same in my mind as an Adkin's diet - I was not expecting more but was certainly surprised by bonus speed on race day.

I definately can relate to all of these :-).

You are forgetting one thing. When you were running the marathon, you are tapered. When you were running your tempo runs you are probably running slightly fatigued due to volume. After the marathon you have depleted glycogen storage and are fatigued. You might have tapered better for this marathon than in the past along with a bigger load prior to the race.

PS- am I the only person who thought this was sexual based on the topic?

I did do the taper different - for this race I did a 2 week taper (roughly cutting from mid 70s pre-taper to mid 50s to mid 20s mpw) instead of a 3 week following Pfitz in prior and during the 2 weeks this time I ran much harder workouts like an short MP run about every day in the final week vs in the 3 week Pfitz most of the runs were slower recovery mileage.

2 wks vs 3 and higher quality workouts - I would have thought from that I would actually make me MORE fatigued in this race in comparison to the prior.

I guess the next couple weeks will show if the MP pace comes back to where it was on race day - I hope it does - but seems after 3 weeks later only coming back to pre-taper pace that going lower will not be forthcoming.

I'd like to bat around a new theory on why it works that was born off some comments on my blog.

Could it be that by doing hard exersizing while fully glucose depleted after a week of low carbs is stressing the muscles causing an adaptation to 1) increase mitochondiral splitting activity which gives more speed and 2) increase the storage load for glycogen which gives more endurance.

It strikes me that this depleted state after the low carbs is much similar to the state at the end of a marathon so adding some stress to the body at this end of marathon type state should help the body to better adapt to the condition.

Seems to be many google hits relating carb depletion and AMPK Activation which I guess leads to the mitochondrial density increases.

I'm dangerously new to these concepts so am probably guilty of using a little bit of info to make incorrect assumptions - that is why I thought I'd test the concept on the expert crowd around here.

Thoughts/reactions?

Does anyone think going through the cab depletion/load plan is worth trying for a half marathon, or is it too short of a race?