Re: satiety and weight loss [was ... HFCS]

[Guest guest]

--- Connie <cbrown2008@...> wrote:

> The " reporting flaws " argument, though, to me does not explain

> studies that have different weight loss outcomes when all groups use

> the same food-reporting mechanism and the same calories. I'm sure

> you've seen the Harvard study where with 3 groups, who each had

> equal calories, but different macronutrient percents, had different

> weight loss outcomes. But of course this one did not control for

> exercise.

> http://www.cnn.com/2003/HEALTH/diet.fitness/10/14/lowcarb.mystery.ap

Connie,

Here's a little more about that study:

Harvard researcher finds dieters eat more, lose more on low-carb plan

http://www.news.harvard.edu/gazette/daily/0310/20-lowcarb.html

==========================================

Though Greene's study didn't allow low-carbohydrate dieters to eat all

they wanted, it still provided extra calories that, somehow, didn't

translate into extra weight.

While some have said her results defy laws of thermodynamics - since

more calories should equal more weight, whatever the calories' source

- Greene said the explanation is obviously more mundane.

It has already been shown that it takes more energy to metabolize

protein than carbohydrate, Greene said, and that may provide a small

part of the answer. Other possibilities are that the body may absorb

less of what's eaten in a low-carbohydrate diet, which is high in

protein and in fat. Whatever the answer, she said, she's sure the laws

of physics still apply.

" I don't think for a minute that anything is violating the laws of

thermodynamics, " Greene said. " [but] there's no smoke and mirrors here. "

==========================================

I think the real challenge for those of us who want to lose weight is

finding a long-term diet that provides satiety at a low enough calorie

level to achieve an ideal weight over time. The actual amount of

calories to achieve an ideal weight will vary from person to person

because of many factors, but if satiety is not maintained at a level

of calories to support the ideal weight then weight loss will not

occur unless we are very strict about measuring the calories we intake

and if we know what calorie level it takes to lose weight. Even Colpo

agrees that low-carb diets are better for promoting satiety with fewer

calories than low-fat diets.

[Guest guest]

On 6/15/08, <oz4caster@...> wrote:

> Even Colpo

> agrees that low-carb diets are better for promoting satiety with fewer

> calories than low-fat diets.

Colpo is a clear and unambiguous proponent of low-carb diets. He was

known primarily for his stance in favor of low-carb diets within the

low-carb community until he posted a picture of his 4% bodyfat abs and

people asked how he stayed so lean and he said the main key to weight

loss was a caloric deficit. He got blasted by the folks who say

low-carbing offers metabolic advantage independent of calories and

exercise, but that didn't make him any less a proponent of

low-carbing. He recommends everyone restrict carbs to 100 g/day at

the very maximum, with some exceptions for post-workout carbs, which

are sometimes very substantial if the exercise is very intense.

Chris

[Guest guest]

--- In , " Masterjohn "

<chrismasterjohn@...>

wrote:

> Colpo is a clear and unambiguous proponent of low-carb diets. He was

> known primarily for his stance in favor of low-carb diets within the

> low-carb community until he posted a picture of his 4% bodyfat abs and

> people asked how he stayed so lean and he said the main key to weight

> loss was a caloric deficit. He got blasted by the folks who say

> low-carbing offers metabolic advantage independent of calories and

> exercise, but that didn't make him any less a proponent of

> low-carbing. He recommends everyone restrict carbs to 100 g/day at

> the very maximum, with some exceptions for post-workout carbs, which

> are sometimes very substantial if the exercise is very intense.

Have you evaluated the studies Colpo cites in favor of his post-workout carbs

and

proteins recommendations? Colpo supports a paleolithic eating regime, but other

supporters of such a regime such as Art De Vany are steadfastly against

consuming post-

workout concoctions.

For example, De Vany in a June 16 blog response says " exercizing in the fasted

state is

the preferred method. That does not preclude a brief fast following the work

out.

Combining the methods puts you into a high GH (growth hormone) state and keeps

you

there. "

http://www.arthurdevany.com/?p=1106#comments

The Colpo and De Vany recommendations are in clear contradiction to each other.

[Guest guest]

,

> Have you evaluated the studies Colpo cites in favor of his post-workout

> carbs and

> proteins recommendations? Colpo supports a paleolithic eating regime, but

> other

> supporters of such a regime such as Art De Vany are steadfastly against

> consuming post-

> workout concoctions.

>

> For example, De Vany in a June 16 blog response says " exercizing in the

> fasted state is

> the preferred method. That does not preclude a brief fast following the work

> out.

> Combining the methods puts you into a high GH (growth hormone) state and

> keeps you

> there. "

I haven't read the studies, but Colpo describes research showing that

post-workout carbs do not lower GH, whereas De Vany in the link you

offer dogmatically states that post-workout fasting increases GH.

Colpo points out that the overall effect of post-workout rise in GH on

body composition has not been demonstrated clearly yet anyway, and De

Vany does not address it. Unless De Vany has scientific support for

his position elsewhere that you can direct me to, it is much more

efficient for me to ignore De Vany and side with Colpo.

Moreover, I find post-workout carbs to be the only logical way of

maximizing glycogen repletion. I certainly do not want to have lower

glycogen stores just because I am low-carbing, and it is

well-demonstrated, as I understand it, that glucose and other

transporters are highly elevated in muscle cells during and 30 minutes

following exercise, making it an ideal time to make sure the carbs get

into the muscles and not elsewhere.

Chris

[Guest guest]

--- In , " Masterjohn "

<chrismasterjohn@...>

wrote:

> Unless De Vany has scientific support for

> his position elsewhere that you can direct me to, it is much more

> efficient for me to ignore De Vany and side with Colpo.

Criticizing post-work out drinks is one of De Vany's favorite topic. However, I

do wish he

included more formal citations in his blog posts. Here is one:

http://www.arthurdevany.com/?p=15

> Moreover, I find post-workout carbs to be the only logical way of

> maximizing glycogen repletion.

De Vany is a believer in the importance of gene expression. He says glycogen

depleting

exercise turns on genes that encourage muscle growth.

http://www.arthurdevany.com/?p=810

http://www.arthurdevany.com/?p=458

http://www.arthurdevany.com/?p=304

[Guest guest]

> Criticizing post-work out drinks is one of De Vany's favorite topic.

Which would make him a man after my own heart, except for after I heard

someone say the only way to read De Vany is in the voice of Captain

Kirk, it is hard to get past the self aggrandizing.

I don't imagine native nutrition included post workout drinks.

Re glycogen regeneration - do you read Eades' blog? There was

a blurb a while back that mentioned that with gluconeogenisis, the new

glucose goes first into replacing glycogen, says a researcher who uses

carbon tracing. So, say if you worked hard not every day but once or

twice a week, you could replenish naturally. (To introduce yet another

writer, Mark Sisson, who says work hard and run hard once in a while).

Not to put down special needs of people who have to work that hard

every day, like laborers or athletes or others whose motivation is

something other than everyday health. (money to live or big glory)

[Guest guest]

,

> Criticizing post-work out drinks is one of De Vany's favorite topic.

> However, I do wish he

> included more formal citations in his blog posts. Here is one:

>

> http://www.arthurdevany.com/?p=15

Well from the abstract he lists, it would appear only the liquid drink

was a problem, as they note no differences between whole food and the

placebo or the " supplemental drink " and the placebo, and they don't

state the composition of anything but the whole food, which contained

75 g carbohydrate. So if you can eat 75 g carbohydrate post-workout

with no ill effect, I'd certainly call that a high-carbohydrate

post-workout snack. I'm sure there's more information in the full

study were one to track it down but I don't really see the point from

what is posted.

>> Moreover, I find post-workout carbs to be the only logical way of

>> maximizing glycogen repletion.

> De Vany is a believer in the importance of gene expression. He says glycogen

> depleting

> exercise turns on genes that encourage muscle growth.

>

> http://www.arthurdevany.com/?p=810

All speculation from cell studies. I agree low-glycogen state is

important, but this can be accomplished through intense exercise, and

then glycogen can get repleted afterwards. In any case, my

understanding is that post-workout meals enhance anabolic gains

according to the research, and rather than hypothesizing based on cell

studies, what he should be doing is citing in vivo human trials of

post-workout carbs and only resorting to the cell studies to explain

what the in vivo trials found.

> http://www.arthurdevany.com/?p=458

He says nothing about the exercise. I'd be inclined to believe it was

not something explosive if the muscle relying on fat failed last and

the high-glycogen muscles failed first. Also, it isn't clear to me

from what he states why this couldn't best be interpreted as refecting

slow-twitch versus fast-twitch fibers. Slow-twtich fibers have more

mitochondria and less glycogen and are designed to endure longer. But

there isn't enough information stated.

> http://www.arthurdevany.com/?p=304

This suggests that it is useful for endurance to continually deplete

glycogen, but doesn't indicate anything to me about post-workout

carbohydrate. Glycogen depletion could be achieved by fasting and/or

low-carbing prior to the workout and working out at such an intensity

as to achieve high depletion in one workout. After that workout, the

post-workout window would still seem the best time to replete the

glycogen.

Chris

[Guest guest]

--- In , " Masterjohn "

<chrismasterjohn@...>

wrote:

> All speculation from cell studies. I agree low-glycogen state is

> important, but this can be accomplished through intense exercise, and

> then glycogen can get repleted afterwards.

I didn't read carefully enough to pick up on the pre vs. post workout

distinction.

> This suggests that it is useful for endurance to continually deplete

> glycogen, but doesn't indicate anything to me about post-workout

> carbohydrate.

He has two more posts with studies cited I just found, but again they seem to be

more

about carbs pre-workout and concurrent with the workout, rather than after the

workout.

http://www.arthurdevany.com/?p=302

http://www.arthurdevany.com/?p=301

> Glycogen depletion could be achieved by fasting and/or

> low-carbing prior to the workout and working out at such an intensity

> as to achieve high depletion in one workout. After that workout, the

> post-workout window would still seem the best time to replete the

> glycogen.

Chapter 13 of Colpo is a bit scary about the threat of gluconeogenesis,

especially if

muscle tissue is used as the source. However, he doesn't cite sources

documenting the

dangers of gluconeogenesis for muscle tissue. Clearly muscle loss is a

theoretical

possibility, but it is a real one?

I suppose I should read references 29-32 in Chapter 13, which Colpo says show

that

consuming carbs post-workout does not reduce the production of growth hormone, a

contradiction to another of De Vany's key claims.

Here is a comment from an online biochemistry textbook about how muscle loss is

prevented during starvation:

" How is the loss of muscle curtailed? After about 3 days of starvation, the

liver forms large

amounts of acetoacetate and d-3-hydroxybutyrate (ketone bodies; Figure 30.17).

Their

synthesis from acetyl CoA increases markedly because the citric acid cycle is

unable to

oxidize all the acetyl units generated by the degradation of fatty acids.

Gluconeogenesis

depletes the supply of oxaloacetate, which is essential for the entry of acetyl

CoA into the

citric acid cycle. Consequently, the liver produces large quantities of ketone

bodies, which

are released into the blood. At this time, the brain begins to consume

appreciable

amounts of acetoacetate in place of glucose. After 3 days of starvation, about a

third of

the energy needs of the brain are met by ketone bodies (Table 30.2). The heart

also uses

ketone bodies as fuel. "

http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=stryer.section.4355

I don't know what to do!

Thanks for the detailed response,

[Guest guest]

,

> I didn't read carefully enough to pick up on the pre vs. post workout

> distinction.

Well, yeah, you wouldn't do pre-workout carbs. That's kind of crazy,

in my opinion, since carbs can be sedating and insulin can counteract

adrenaline in important tissues.

>> This suggests that it is useful for endurance to continually deplete

>> glycogen, but doesn't indicate anything to me about post-workout

>> carbohydrate.

>

> He has two more posts with studies cited I just found, but again they seem

> to be more

> about carbs pre-workout and concurrent with the workout, rather than after

> the workout.

>

> http://www.arthurdevany.com/?p=302

> http://www.arthurdevany.com/?p=301

Colpo never recommends pre-workout carbs, but does recommend

during-workout carbs when the workout is very intense and longer than

45 minutes for the sake of maintaining performance. In my experience,

this can be useful if one wants to ensure gains over the previous

performance for weightlifting.

>> Glycogen depletion could be achieved by fasting and/or

>> low-carbing prior to the workout and working out at such an intensity

>> as to achieve high depletion in one workout. After that workout, the

>> post-workout window would still seem the best time to replete the

>> glycogen.

> Chapter 13 of Colpo is a bit scary about the threat of gluconeogenesis,

> especially if

> muscle tissue is used as the source. However, he doesn't cite sources

> documenting the

> dangers of gluconeogenesis for muscle tissue. Clearly muscle loss is a

> theoretical

> possibility, but it is a real one?

I don't think gluconeogenesis is a major player till glycogen is

depleted. That shouldn't be a major issue during exercise. Even when

fasting, fasting mostly depletes liver glycogen whereas activity

depletes muscle glycogen. That said, Colpo recommends pre-workout

whey protein, which should provide the necessary aminos for what

gluconeogenesis does occur.

Chris

[Guest guest]

and

> >> This suggests that it is useful for endurance to continually deplete

> >> glycogen, but doesn't indicate anything to me about post-workout

> >> carbohydrate.

> >

> > He has two more posts with studies cited I just found, but again

they seem

> > to be more

> > about carbs pre-workout and concurrent with the workout, rather

than after

> > the workout.

> >

> > http://www.arthurdevany.com/?p=302

> > http://www.arthurdevany.com/?p=301

FWIW, in that second article he does appear to be implicating

post-workout carbs: " You reduce the magnitude of the adaptive response

to exercise if you are in a hurry, as so many body builders and

runners are, to replenish your glycogen stores. They are not thinking

at all about gene signaling and adaptation. They are in the linear

thinking mode and must reason in a simple (dumb) inventory framework.

Use up the glycogen and refill it right away. "

> Colpo never recommends pre-workout carbs, but does recommend

> during-workout carbs when the workout is very intense and longer than

> 45 minutes for the sake of maintaining performance. In my experience,

> this can be useful if one wants to ensure gains over the previous

> performance for weightlifting.

In my experiences in endurance athletic events, carbohydrates are

absolutely essential to good performance for intense exercise lasting

greater than 30-60 minutes. Near-maximal aerobic exertion requires

glycogen breakdown because fat oxidation cannot yield energy at as

high a rate. Unless there's some way to train your body to

*drastically* increase its fat oxidation ability, there is no avoiding

the necessity of carb intake during extended intense activity.

However, during a 45-minute weight-training session, you've got plenty

of downtime between weights/machines so you can avoid ingesting any

carbs (and I do). But I wonder what Art De Vany thinks endurance

athletes can do to avoid carbs during exercise without sacrificing

performance!

Tom

[Guest guest]

> But I wonder what Art De Vany thinks endurance

> athletes can do to avoid carbs during exercise without sacrificing

> performance!

De Vany hates endurance sports like long-distance running. He thinks they are

killing

peoples. He loves to point every article about an endurance athelete dying of

heart disease or

cancer. There are a long list of posts on " death by exercise " and related topics

at

http://www.arthurdevany.com/endurance_training_death_injury_and_risk/

He also dislikes their body shapes, feeling that they should be more muscular.

De Vany is OK with running sports such as sprinting. I weight train twice a week

and do some

occasional sprinting.

[Guest guest]

> carbs (and I do). But I wonder what Art De Vany thinks endurance

> athletes can do to avoid carbs during exercise without sacrificing

> performance!

>

> Tom

Tom, he suggests that endurance athletes adapt to fat-burning. I

assume you've seen the study by Phinney that low carbers use to show

you don't have to use carbs for endurance exercise. The main thing is

to allow for adaptation. And after that, only sprinting really needs

fast glycogen replacement if you do it frequently, but not endurance

exercise...

" Phinney described studies conducted on professional

(trained) bicyclists as well as untrained individuals (these didn't

ride a bike but exercised on a treadmil) and their performance under

a very low carbohydrate diet. Their performace decrease during the

first weeks, as expected, but it recover after about 4-6 weeks on

what they call a 'ketogenic diet' which is strictly speaking a very

low carbohdyrate diet (no downtime in training); their performance

(i.e. endurance) even increased after that.

This is, at a glance, how the studies were conducted:

D Phinney. Ketogenic diets and physical performance.

Nutrition & Metabolism 2004, 1:2 (emphasis is mine)

This second study utilized competitive bicycle racers as subjects,

confined to a metabolic ward for 5 weeks. In the first week, subjects

ate a weight maintenance (eucaloric) diet providing 67% of non-

protein energy as carbohydrate, during which time baseline

performance studies were performed. This was followed by 4 weeks of a

eucaloric ketogenic diet (EKD) providing 83% of energy as fat, 15%

as protein, and less than 3% as carbohydrate (this is as close to the

Inuit diet as it gets). The meat, fish, and poultry that provided

this diets protein, also provided 1.5 g/d of potassium and was

prepared to contain 2 g/d of sodium. These inherent minerals were

supplemented daily with an additional 1 g of potassium as

bicarbonate, 3 grams of sodium as bouillon, 600 mg of calcium, 300 mg

of magnesium, and a standard multivitamin.

And at a glance, what they observed (I'll write here only the part

regarding the bicyclists):

S.D. Phinney. Nutrition & Metabolism 2004, 1:2 (emphasis is mine)

The bicyclist subjects of this study noted a modest decline in their

energy level while on training rides during the first week of the

Inuit diet, after which subjective performance was reasonably

restored except for their sprint capability, which remained

constrained during the period of carbohydrate restriction. On

average, subjects lost 0.7 kg in the first week of the EKD, after

which their weight remained stable. Total body potassium (by 40K

counting) revealed a 2% reduction in the first 2 weeks (commensurate

with the muscle glycogen depletion documented by biopsy), after which

it remained stable in the 4th week of the EKD. These results are

consistent with the observed reduction in body glycogen stores but

otherwise excellent preservation of lean body mass during the EKD

(this is one of the risks of neglecting the nutritional part in which

protein intake is a key component.

The endurance exercise test on the cycle ergometer was performed at

65% of VO2max, which translates in these highly trained athletes into

a rate of energy expenditure of 960 kcal/hr. At this high level of

energy expenditure, it is notable that the second test was performed

at a mean respiratory quotient of 0.72, indicating that virtually all

of the substrate for this high energy output was coming from fat.

This is consistent with measures before and after exercise of muscle

glycogen and blood glucose oxidation, which revealed marked

reductions in the use of these carbohydrate-

derived substrates after adaptation to the EKD.

Examining the results of these two ketogenic diet performance studies

together indicates that both groups experienced a lag in performance

across the first week or two of carbohydrate restriction, after which

both peak aerobic power and sub-maximal (60–70% of VO2max) endurance

performance were fully restored. In both studies, one with untrained

subjects and the other with highly trained athletes who maintained

their training throughout the study, there was no loss of VO2max

despite the virtual absence of dietary carbohydrate for 4–6 weeks.

This whole-body measure of oxidative metabolism could not be

maintained unless there was excellent preservation of the full

complement of functional tissues including skeletal muscle (and

mitochondrial) mass, circulating red cell mass, and cardiopulmonary

functions.

>