Carb Deplete and Load

You are not going to increase mitochondrial density very much over 10 days if you are already decently well trained.

Also, I am not aware of a mechanism that would increase red cell mass or oxygen carrying capacity.

Fat mass loss even over 10 days would probably not be much. You lost a lot of weight from the lack of muscle glycogen and the loss of the water that is stored with it.

Maybe changing the taper led to the performance improvement. This is a problem with using an n of 1 and why studies like to have large numbers of people including a control group.

Sherman showed quite clearly that to load the muscles with glycogen one does not need to deplete and that depleting oneself can negatively affect workouts. The downside here is that you could potentially detrain especially if you did it for 10 days (which if I recall is far longer than at least research studies have done). It can only take a few hard and/or long workouts to get muscle glycogen pretty low (one never really depletes it under most conditions--i.e., outside of a starvation situation).

Louise Burke at AIS has some research suggesting that reduces carbs can actually impair oxidative processes in using glycogen. It is still early on that front, but she is a damn fine researcher and practitioner.

Other potential factors in your performance improvement (since you did not give more detail):

* Experience--you had at least one marathon under your belt. Do not underestimate the benefits of experience in everything from better sleep the days before to pacing. I changed little in my training from running 3:09 to 3:01. Better feeding before and during the marathon along with better hydrating can make a difference.

* The course--was the faster marathon run on a more "friendly" course? Terrain can make an impact.

* Training--just having the additional miles added onto your previous training can be impactful. This kinda goes along with experience.

* Weather: a cooler marathon can be a big help. Going from a marathon run in the 60s to one in the low 50s can have a huge impact.

* Confidence--this goes along with experience.

I am probably forgetting or neglecting some things, but it is late.

Ok, so I am in sports nutrition, taught by a recreational runner, and this is directly from her powerpoint lecture on carb loading:

Carbohydrate Loading Methods:

1) 6 days prior – exhaustive exercise and low carbohydrate x 3 days; high carbohydrate x 3 days and rest(1)

2) 6 days prior – exhaustive exercise and mixed diet x 3days; high carbohydrate x 3 and rest(2)

3) Possibly, 24 hours prior, 3 minute high intensity exercise followed by 10 g CHO/kg (3)

1 Bergstrom, 1967; 2 Sherman, 1981; 3 Fairchild, 2002

Who would benefit?

Endurance athletes (more than 90 minutes)

Stop and go sports

Tournaments

There was an accompanying graph by Shurman and Costill, 1984, but you can't put graphs on this blog...

luv2run - thanks for taking the time to respond.

luv2run wrote:

You are not going to increase mitochondrial density very much over 10 days if you are already decently well trained.

Also, I am not aware of a mechanism that would increase red cell mass or oxygen carrying capacity.

Fat mass loss even over 10 days would probably not be much. You lost a lot of weight from the lack of muscle glycogen and the loss of the water that is stored with it.

So you've knocked out all my theories.

luv2run wrote:Maybe changing the taper led to the performance improvement. This is a problem with using an n of 1 and why studies like to have large numbers of people including a control group.

if only I had a clone - part of my motive in posting is selfish - as I likely only have less than 10 good marathons in me - the experimentation of 1 is quite limitted - if I can get the benefits of others experiences...

luv2run wrote:Sherman showed quite clearly that to load the muscles with glycogen one does not need to deplete and that depleting oneself can negatively affect workouts. The downside here is that you could potentially detrain especially if you did it for 10 days (which if I recall is far longer than at least research studies have done). It can only take a few hard and/or long workouts to get muscle glycogen pretty low (one never really depletes it under most conditions--i.e., outside of a starvation situation).

so the 10 day was not tested - there was a 3-4 day period at the end of the 10 days where workouts definately suffered - for marathon paced heartrate - my workout pace dropped to around 7 mpm from 6:20ish. This was the part I was wondering about - if stressing the body while under this depleted state for several days - which I did - M-Paced runs each day - created an extra adaptation of sorts that gives the extra benefit on race day - sounds like Sherman doesn't address - I did not see my running speed drop in the first 5 days so if his test stops there - it does not address that question.

luv2run wrote:Louise Burke at AIS has some research suggesting that reduces carbs can actually impair oxidative processes in using glycogen. It is still early on that front, but she is a damn fine researcher and practitioner.

Don't know anything about this - wondering on the surface if relavent since there was the 3 day carb loading before the race - so plenty of carbs around on raceday.

Other potential factors in your performance improvement (since you did not give more detail): More details can be found reading thru more of the blog but I'll summarize my background regarding what you asked here.

* Experience--you had at least one marathon under your belt. Do not underestimate the benefits of experience in everything from better sleep the days before to pacing.

My running background.

- I'm 40 yrs old now and for marathons I started with a 4:28 1/06 Houston, 3:10 1/07 Houston, 3:01 4/07 Boston, 2:56 11/07 NYC, 1/08 2:40 Houston. Several other races of all distances 5k-30k mixed in especially over last 1.5 yrs.

- Alghough NYC to Houston was 16 minutes improvement - I am only crediting 6-7 minutes to this deplete/load thing. I had several indications I was likely 2:47 capable including 5k,10k and 30k race times and training logs showing around 6:20-25 pace for what I use as my marathon heartrate. That is also currently my MP pace ~6:20 - 4 weeks since Houston what I am getting for my marathon heartrate as of a 9 mile marathon paced run yesterday. I've got a 1/2 marathon next weekend and I'm sitting here wondering if I can sub1:20 for it based on how fast I am today - I think I can.

* The course--was the faster marathon run on a more "friendly" course? Terrain can make an impact. I gave 2 minutes credit for NYC to Houston difference basis McMillan Calculator.

* Training--just having the additional miles added onto your previous training can be impactful. This kinda goes along with experience. I gave about 6 minutes credit for training improvements in the 10 weeks between the races - I can see this improvement in my training logs.

* Weather: a cooler marathon can be a big help. Going from a marathon run in the 60s to one in the low 50s can have a huge impact. Weather essentially the same - NYC 55F 11 mph winds, 49F 12 mph winds.

* Confidence--this goes along with experience. The mental edge definately goes to Houston - I felt sharper - I live in Houston and had run 2 times before so familiarity factor was high too - but 6-7 minutes faster from confidence?

Anyway - I know skeptism on one data point will alway be high - I doubt it myself until I can see repeated in others or especially myself - but I think I do know my speeds and I just don't run as fast as I did at Houston - never have before or since and whatever was going on I want to be sure I can replicate it again.

cheers - John.

runkeller wrote:

Ok, so I am in sports nutrition, taught by a recreational runner, and this is directly from her powerpoint lecture on carb loading:

Carbohydrate Loading Methods:

1) 6 days prior – exhaustive exercise and low carbohydrate x 3 days; high carbohydrate x 3 days and rest(1)

2) 6 days prior – exhaustive exercise and mixed diet x 3days; high carbohydrate x 3 and rest(2)

3) Possibly, 24 hours prior, 3 minute high intensity exercise followed by 10 g CHO/kg (3)

1 Bergstrom, 1967; 2 Sherman, 1981; 3 Fairchild, 2002

Who would benefit?

Endurance athletes (more than 90 minutes)

Stop and go sports

Tournaments

There was an accompanying graph by Shurman and Costill, 1984, but you can't put graphs on this blog...

Thanks for the reference sources so I can go back and research a little. I know of a guy that did #3 at Dallas recently on his first marathon ever and got a Sub3 with power to the end.

I would add that Bussau published a paper in 2002 I think showing a one day loading protocol with 10g/kg (that is a lot BTW). The subjects did no exercise at all and they loaded up pretty well. There was no performance measurement done. The study was actually looking to see if 3 days of such a protocol would pack in more glycogen. There was no exercise during those days. (3 days did not significantly improve muscle glycogen).

The subjects were cyclists and triathletes with Vo2max of ~60 ml/kg/min.

Kayry you appear to have some above average talent for

the sport considering your age and background.

One of the "big name" proponents of carbohydrate loading

in the past was the British Runner Ron Hill. He was one

of the first big name runners that had success with the

Saltin Diet. He has a blog and a website for his British

clothing company.

You might want to get his two books, one was "The Long Run"

or something similar. You could probably find his email address on his blog.

"The Long Hard Road" - Ron Hill - difficult to find - cheapest I've found is $150. I'll keep searching for the blog.

PM your edress and I'll send you the link.

I do not know how to get the link on this thread.

Hi all - I read this thread and all of your comments before my last marathon (Boston, 2013 -a tragic ending to the day - but I did want to mention how the run went here as this thread played a role). This discussion got me curious to see if carb depletion could help with my carb loading. This was my 9th marathon, my PR was 3:04:05 at Baystate (fast, flat course) last fall. During that race I was on pace for a sub-3 run until mile 20 and then bonked pretty well in the last six miles. Didn't feel like a leg issue, pure fuel problem. So this time I really wanted to change everything about my fueling strategy (also added 10 miles a week or so to peak training, from 50-60). I carb depleted (full on, Atkins style) for 7 days, during which I ran four utterly miserable carb-depleted workouts. Then I carb loaded for four days. Have never felt so strong during the last six miles of a marathon. Legs of course got more and more tired, but I had fuel all the way to the end. Almost perfectly even split timewise (though with the hills in the second half of Boston, I think that's a more intense effort in second half, conceptual equiv of negative split?). Fastest mile was 22. Finished in 2:58:43, a pretty decent PR over last fall's run. So I'm not sure if it's due to the carb depletion or not, but the result was such that I'm going to continue the experiment for the next one.

I've had success in carbohydrate loading starting three days before the marathon eating 4g/lb of bodyweight in carbs. So in my case I shoot for 600g of carbs / day 3 days out although the day before the marathon I usually eat lighter 450-500g of carbs. I try to take in 80-90% of my calories in carbs during this period. I have tried to restrict the carbs leading up to this window but havent found any difference in my case (eating normal vs restricting).

The other aspect here that I don't see discussed is the benefit of glycogen depleting runs. For example, I'll often run 13-18 miles on a weekday morning on a completely empty stomach and not take any food with me. I don't have scientific research but truly think it has helped me tremendously, especially later in marathons.