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Depriving your body of sugar to raise efficiency?

phourgenres

Apr 28, 12 18:14

Post #1 of 15 (1541 views)

Depriving your body of sugar to raise efficiency?	Quote \| Reply

I've heard there were a couple studies done on this topic (which actually turned up favorable results), but I mainly made this thread to see if it was used very often with competitive athletes.

The idea is that by depriving your body of sugars during training, it forces your body to go into fatty acid oxidation quicker. I have even heard of people fasting for 8 hours (not eating breakfast) and going out ride to accomplish this even more efficiently. During high intensity exercise a very conditioned athlete taps into his fatty acid storage rather than totally depleting his glycogen storage. This then allows his glycogen storage to be more readily available throughout a longer period in the race.

When building a solid aerobic base, isn't raising our bodies metabolic efficiency one of the main things we are trying to accomplish?

(This post was edited by phourgenres on Apr 28, 12 18:15)

AwesomePossum

Apr 28, 12 19:00

Post #2 of 15 (1509 views)

Re: Depriving your body of sugar to raise efficiency? [phourgenres] [In reply to]	Quote \| Reply

Assuming training in a fasted state required longer recovery times, wouldn't simply training more frequently as allowed by "traditional" nutrition be better for the goal you stated? (i have no idea)

HXB

Apr 28, 12 19:34

Post #3 of 15 (1463 views)

Re: Depriving your body of sugar to raise efficiency? [phourgenres] [In reply to]	Quote \| Reply

My opinion is that this is a bit of a chicken and egg situation. I personally don't believe that fasting necessarily is a good or smart thing to do given that you want to race in a completely "sugared up state". I also think it would take a lot of fasting to make an appreciable difference in your body's use of fuel not to mention making any intensity much more difficult and inhibiting the total amount of work you can do before, during and after the exercise session. I believe that for many people, this sort of training will make you better at exercising at low blood sugar levels which could make someone believe they are more efficient. Noakes touches on this fact in "Lore of running" specifically with regard to his Central Governor Model of exercise. Superior athletes use more fatty acids at higher intensities because they have bigger aerobic engines and can deliver the necessary oxygen to burn fatty acids, thus I think in this "chicken and egg" scenario that the engine determines the fuel and not the other way around. If you exercise at your appropriate aerobic level, you should burn a huge majority of fatty acids anyway. These are my opinions based on my experiences, interesting topic.

KssanDR

Apr 28, 12 19:37

Post #4 of 15 (1454 views)

Re: Depriving your body of sugar to raise efficiency? [phourgenres] [In reply to]	Quote \| Reply

It would be nice if someone could scrounge a link up to those studies you mention because they were very informative. Its been a few years since they went around as this idea has been out awhile. It's not so much that your body goes into fat stores faster per se but you can 'train' to become more efficient at it, therefore reserving glycogen stores longer and having to take in fewer calories on those all out endurance efforts. Train being in quotes because its not really the training that comes to mind for most. The ceiling for this effect is reached in a matter of weeks and unfortunately is not as drastic as one would hope, but significant. IMO it should take back seat to getting in quality workouts. This likely isn't a situation where the more the better. Fasting all night and all day then getting in a workout probably wouldn't be any more beneficial than a workout first thing in the morning without breakfast. This is one of the reasons the mantra of not eating before\during a workout shorter than a hour came from.

mojozenmaster

Apr 28, 12 19:50

Post #5 of 15 (1434 views)

Re: Depriving your body of sugar to raise efficiency? [phourgenres] [In reply to]	Quote \| Reply

The idea is that by depriving your body of sugars during training, it forces your body to go into fatty acid oxidation quicker. I have even heard of people fasting for 8 hours (not eating breakfast) and going out ride to accomplish this even more efficiently.

That's why it's called "Breakfast" = you break your fasting period = while you were sleeping when you wake up and eat something.

However, do not believe all of that bullshit about small meals or not eating before bedtime. If you are training hard enough dinner is your biggest meal of the day as it extends your fasting period far beyond waking up.

**All of these words finding themselves together were greatly astonished and delighted for assuredly, they had never met before**

dave_voyageur

Apr 28, 12 20:04

Post #6 of 15 (1411 views)

Re: Depriving your body of sugar to raise efficiency? [phourgenres] [In reply to]	Quote \| Reply

The scientific literature shows that performance is not improved through carbohydrate starving:
http://www.ncbi.nlm.nih.gov/pubmed/16357078

This topic has been discussed elsewhere too:
http://forum.slowtwitch.com/...ing_concept_P3312816

JFinnigan

Apr 28, 12 20:38

Post #7 of 15 (1376 views)

Re: Depriving your body of sugar to raise efficiency? [dave_voyageur] [In reply to]	Quote \| Reply

dave_voyageur wrote:

Evidence yes, but I wouldn't say that an 8d study period warrants dismissing the idea of CHO limitation out of hand. It wouldn't be unreasonable to suggest that the adaptation period may be longer than a week.

ipull400watts

Apr 28, 12 20:41

Post #8 of 15 (1370 views)

Re: Depriving your body of sugar to raise efficiency? [JFinnigan] [In reply to]	Quote \| Reply

Here is some research I have done on fasted training: http://www.runningonthewhiteline.com/...while-in-fasted.html
___
http://www.RunningOnTheWhiteLine.com
SoMe Coordinator at http://www.SkoraRunning.com

BrianPBN

Apr 28, 12 21:25

Post #9 of 15 (1338 views)

Re: Depriving your body of sugar to raise efficiency? [phourgenres] [In reply to]	Quote \| Reply

You may find this article helpful as well....

http://www.personalbestnutrition.com/...BB.pl?num=1275047870

---
Brian Shea
http://www.PersonalBestNutrition.com
http://twitter.com/PBNutrition
1st Endurance, Bonk Breaker, Ironman Perform, CarboPro, etc...
Slowtwitch Discount Code: STWITCH

dave_voyageur

Apr 29, 12 5:31

Post #10 of 15 (1184 views)

Re: Depriving your body of sugar to raise efficiency? [JFinnigan] [In reply to]	Quote \| Reply

Did you read the paper? Not just one 8-day study. Louise Burke has spent many years studying the phenomenon.

Quote 1: "Nevertheless, the effect of various �dietary periodization� on exercise performance has remained unclear, with studies reporting benefits (9), no change (1, 3, 4), or impairment (7, 8) to various endurance and ultraendurance protocols."
Quote 2: "However, there is now evidence that what was initially viewed as �glycogen sparing� after adaptations to a fat-rich diet may be, in fact, a downregulation of carbohydrate metabolism or �glycogen impairment.�

As for the links, stellar internet stuff.
http://www.runningonthewhiteline.com/2012/01/endurance-training-while-in-fasted.html - Spends plenty of time summarizing 4 studies (ok, good start), none of which show a clear benefit on performance from training in the fasted state (not surprising), only to finish off by concluding that it's a good idea and then lists a bunch of bogus potential benefits from some other website to justify his conclusion.
http://team.firstendurance.com/page/low-carbo-training-1 - To quote: "Athletes cannot consume carbohydrates at the same rate they can burn carbohydrates. So when the exercise bout is long enough glycogen stores are depleted and exercise performance suffers. The theory is that depleting glycogen during specific exercise bouts allows the body to become more efficient at utilizing fat. It can take many weeks for the body to adapt to low glycogen levels. The downside is that with low glycogen levels it is difficult to conduct high intensity training sessions since these require glycogen (carbohydrates) almost exclusively. What the researchers propose is varying the intensity and the diet so high intensity exercise bouts are done with high glycogen content and long slow endurance training sessions are done with low glycogen content. This will help the body adapt to a more efficient substrate utilization that can correlate to a sparing glycogen and enhanced endurance. This ability to sustain endurance with a higher reliance on fat utilization through training adaptation can play a key role in reducing gastric distress associated with the need to consume high levels of carbohydrates for long endurance sessions like Ironman, Ultra running or Century rides."

Ok, so according to this mostly unreferenced post, athletes burn CHO faster than they could ever consume them and that it can take many weeks for the body to adapt to low glycogen levels (not really, it's called ketosis). The author then advocates training in a glycogen depleted state for LSD sessions and in a high glycogen state for high-intensity intervals. This is all very confusing - if you eat high-CHO foods, wouldn't you be disrupting the adaptations that take "weeks" to achieve? Furthermore, if you can't possibly consume enough CHO to keep up with the rate you burn, then why starve yourself? Just go for a 4-hour bike ride, you'll achieve a glycogen-depleted state even while consuming CHO. If you don't consume CHO, then you'll bonk and be forced to ride at minimal intensity just to drag yourself home. Doesn't sound like quality training to me...

As with most "novel" ideas for improving performance, fasted training sounds appealing and can be justified by citing a narrow set of studies and by contorting physiological concepts but its benefits are equivocal at best. Just train folks, you'll achieve a glycogen-depleted state on your 4-hour rides and learn to burn your-already-massive fat stores just fine.

S McGregor

Apr 29, 12 5:51

Post #11 of 15 (1148 views)

Re: Depriving your body of sugar to raise efficiency? [dave_voyageur] [In reply to]	Quote \| Reply

dave_voyageur wrote:

Did you read the paper? Not just one 8-day study. Louise Burke has spent many years studying the phenomenon.

That would be asking a bit much don't you think?

Steve

http://www.PeaksCoachingGroup.com

dave_voyageur

Apr 29, 12 6:06

Post #12 of 15 (1124 views)

Re: Depriving your body of sugar to raise efficiency? [S McGregor] [In reply to]	Quote \| Reply

Especially when there's so many fun and self-affirming blogs to read!

S McGregor

Apr 29, 12 6:15

Post #13 of 15 (1105 views)

Re: Depriving your body of sugar to raise efficiency? [dave_voyageur] [In reply to]	Quote \| Reply

dave_voyageur wrote:

Especially when there's so many fun and self-affirming blogs to read!

Thank goodness we have the internet or we might have to rely on the literature and facts.

Steve

http://www.PeaksCoachingGroup.com

dave_voyageur

Apr 29, 12 6:21

Post #14 of 15 (1093 views)

Re: Depriving your body of sugar to raise efficiency? [S McGregor] [In reply to]	Quote \| Reply

My compliments to you for fighting the good fight over here, by the way:
http://forum.slowtwitch.com/..._reply;so=ASC;mh=25;

S McGregor

Apr 29, 12 6:33

Post #15 of 15 (1072 views)

Re: Depriving your body of sugar to raise efficiency? [dave_voyageur] [In reply to]	Quote \| Reply

dave_voyageur wrote:

My compliments to you for fighting the good fight over here, by the way:
http://forum.slowtwitch.com/..._reply;so=ASC;mh=25;

Back to the future.

Steve

http://www.PeaksCoachingGroup.com