Heart Rate Monitor findings. - Page 3

"David Martin" <d.m.a.martin@dundee.ac.uk> wrote in message
news:BC62D6D7.E812%d.m.a.martin@dundee.ac.uk...
> On 25/2/04 7:06 pm, in article c1irna$5qo$1@sparta.btinternet.com, "W K"
> <hyagillot@tesco.net> wrote:
>
> >
> > "David Martin" <d.m.a.martin@dundee.ac.uk> wrote in message
> > news:BC629422.E7C0%d.m.a.martin@dundee.ac.uk...
> >
> >> Well I'll just pop over the road and talk to my colleagues who are
world
> >> leaders in exercise metabolism and metabolic disorders.
> >
> > I imagine that this means that you are not actually a biochemist etc. !
>
> Protein chemist/bioinformaticist currently working on metabolic pathway reconstruction.
>
> >> And if you think the comment about eating directly after exercise is funny, I suggest
you
> > go
> >> and read the appropriate literature.
> >
> > Is this all foods, or are you actually talking about glycogen uptake?
>
> Glycogen isn't taken up, it is synthesised in the cell.

I did use the wrong word there. but you avoid the real question ...

> > If you don't replenish that, you won't be doing much exercise.

... which is that. Anything positive to say on that one? Its a key point to what makes a practical
difference to cyclists. The comment "Energy adsorption is maximal in the 30-60 minutes after
exercise" , will be replenished sooner or later, and its better that it should be sooner if you want
to do any more cycling in the near future.

> >> 1: glycogen breakdown without oxygen :- this leads to lactic acid
buildup
> >> which will rapidly (5-10 mins scale) render you unable to move as you
will
> >> be in oxygen debt, have massive lactic acid build up and the muscles
will
> >> give up.
> >
> > well, glucose really, but thats a moderate nit-pick
>
> talking about glycogen stores being broken down to give glucose. this is then consumed
> anaerobically.

Fair enough. I did say it was a nit pick.

> >> 2: aerobic glycogen breakdown :- sustainable till the glycogen runs
out,
> >> then you bonk
>
> likewise but aerobically.
> >>
> >> 3: glucogenesis from fat :- sustainable relatively indefinitely (ie all day).
> >
> > You keep talking about that. its a minor thing, thats used very
specifically
> > for things that need glucose like the brain. That is not the correct term for "running on fat"
> > that muscles do if
they
> > have plenty of oxygen (ie lower exercise rate)
> >
> >> The speed of glucose production is 1>2>3. If you take pure glucose (ie
in
> > an
> >> 'energy drink' or somesuch) you will slow down glucogenesis from
glycogen
> >> and fat, leading to a slump in energy worse than before taking the supplement as you have to
> >> restart the glucogenesis.
> >
> > Hmmm. That doesn't sound too familiar. Your terms seem all mixed up. surely "glucose consumption
> > 1>2>3", not "production".
>
> Well, as you need to produce glucose from reserves in order to maintain
any
> sort of steady state then glucose production should more or less equal glucose consumption.

Ah, I see. I looked up "glucogenisis" and it had several meanings [one of which was "call it
glycolysis".] Ah, I don't see. You have blood glucose being produced from fat.

> > I don't know why you bring up drinking "pure glucose" (sic), that
sounds
> > like its got a lot more to do with insulin and control of the amount of blood sugar.
>
> And blood sugar gives rise to replenishment of energy stores in the
muscles.
> So if blood sugar drops - the body has to release more. If blood sugar
goes
> up, the body closes down glucose production.

Yes, all that stuff being controlled by insulin etc. Not sure about the word "production" there
though, but thats one of semantics. [Oh no... you aren't actually suggesting that blood glucose is
being produced from fat are you???!]

> > By the way - do you actually know the meaning of "glucogenesis" - it
seems
> > to be a confused term that means many things and nothing at the same
time.

[Ok ... and its what I think I'd have called "glycolysis"]

> >> well, seeing as fat biosynthesis is from glucose, and dietary fat has relatively little effect
> >> on fatty tissue build up (compared to carbs)
> >
> > uh oh, atkins stuff. Where does the fat you eat go when you eat too
much.
>
> Well, it was shown many many years ago that dietary fat (ie the fats and oils you eat in your
> food) does not create the fat that sits in the spare tyre or so without passing through part of
> the same metabolic route as the products of carbohydrate breakdown. I don't have a copy of
> metabolic pathways to hand (it is at work and I am at home and away from the lab for
a
> few days) otherwise I'd quote more specifically.

you aren't on about acetyl CoA are you? You seem to be more concentrating on the details of the
metabolic paths rather than when and where - or if - it happens. There is still the basic question -
where does the fat you eat go when you eat too much. OK, it _IS_ broken down into 2 carbon units and
then rebuilt in the apidose - but knowing it does not happen directly without these stages does not
get any further to answer the when/where/if questions more relevant to a fat cyclist.

And again the "compared to carbs" bit is more a question of hormones than metabolic pathways.

> And apart from that which goes straight through, biosynthesis into a
number
> of different things including (eventually) fatty acids.
>
> >> and as carbs will inhibit glucogenesis from fat (feedback inhibition through activation of
> >> various kinase signalling cascades by binding of the appropriate kinases to glycogen phosphate)
> >
> > Do you actually understand that excess detail there.
> Yes. I had lunch today with the people who discovered a lot of these
control
> cascades.

Illogical ...I've had more than one meal with a chess champion, and I've only ever beaten a
10 year old.

I now realise as well, that you are mixing up meanings and different levels of scientific
terminology. ie - the mega-technical + the inaccurate. You have also used two vastly different
meanings of the word "glucogenisis".

You don't seem to know what you are talking about at all.

> > Strikes me as science being warped into psuedo science. <atkins alert!>
>
> The atkins diet works for some but not for the reasons atkins puts
forward.
> I wouldn't support it as a suitable diet. However, I don't believe that a high carb, low fat diet
> is any better. Moderation, plenty of fruit and veg and making sure you balance input and output
> are the key things in a good diet.

That the diet might work does not mean the psuedoscience is fact.

W K wrote:
>
>
>> > If you don't replenish that, you won't be doing much exercise.
>
> ... which is that. Anything positive to say on that one? Its a key point to what makes a practical
> difference to cyclists. The comment "Energy adsorption is maximal in the 30-60 minutes after
> exercise" , will be replenished sooner or later, and its better that it should be sooner if you
> want to do any more cycling in the near future.

He only said that eating after execise was not a good way to lose weight, because the food will be
absorbed quickly. If you're an endurence athlete, then eating to replenish ASAP is a good thing, if
you're a bloater looking to maximise weight loss without feeling hungry, it's bad.

I said:

> but as soon as I start running I feel as though I'm reading water

That shoud of course have been _treading_ water. :-)

--
Dave...

David Martin <d.m.a.martin@dundee.ac.uk> wrote in message news:<BC629422.E7C0%d.m.a.martin@dundee.ac.uk>...

> Well if I exercise as hard as I can I can't keep that up for eight hours. It is about maximising
> long term burn. There is little point in knackering yourself with inappropriate exercise.

I think what 2Lap is suggesting is a controlled expenditure of energy so that it is maximised over
the available exercise period, not a flat out effort then trying to hold that level for 8 hours. In
other words ride like a time triallist, rather than an outclassed road racer desperately trying to
hang on to the bunch. I actually don't agree with it as a viable strategy for every ride; I'm just
trying to get the point straight. 2Lap?

--
Dave...

David Martin <d.m.a.martin@dundee.ac.uk> wrote in message news:<BC62D6D7.E812%d.m.a.martin@dundee.ac.uk>...

> And blood sugar gives rise to replenishment of energy stores in the muscles. So if blood sugar
> drops - the body has to release more. If blood sugar goes up, the body closes down glucose
> production.

I may be out of date here, but I thought the immediate cause of rebound hypoglycaemia, and the
reason it's not a good idea to try to boost energy with direct consumption of sucrose or
glucose, was simply the body's production of insulin in response to the rise in the blood sugar
level. You get an immediate boost but in a few minutes your blood sugar level is lower than it
was when you started.

> Moderation, plenty of fruit and veg and making sure you balance input and output are the key
> things in a good diet.

With all the jargon cut out, there is some really sound advice.

--
Dave...

"Simian" <Simian@in_valid.semi-evolved.org> wrote in message
news:103rdie54g38p0a@news.supernews.com...
> W K wrote:
> >
> >
> >> > If you don't replenish that, you won't be doing much exercise.
> >
> > ... which is that. Anything positive to say on that one? Its a key point to what makes a
> > practical difference to cyclists. The comment "Energy adsorption is maximal in the 30-60 minutes
> > after exercise" , will be replenished sooner or later, and its better that it should be sooner
> > if you want to do any more cycling in the near future.
>
> He only said that eating after execise was not a good way to lose weight, because the food will be
> absorbed quickly. If you're an endurence athlete, then eating to replenish ASAP is a good thing,
> if you're a bloater looking to maximise weight loss without feeling hungry, it's bad.

He didn't actually mention whether this was food in general (something I've not really seen anything
about), or for the building up of glycogen (standard sport physiology).

If it is the building up of glycogen, then its not an option. You can lose your 500grams of glycogen
by doing as you describe, but this will not give you long term weight loss if thats what you are
trying to do. That is very easy weight to lose, and why an atkins diet starts off so very well.

It doesn't follow immediately that losing your glycogen will be followed up by losing your fat.

W K wrote:
>
> "Simian" <Simian@in_valid.semi-evolved.org> wrote in message
> news:103rdie54g38p0a@news.supernews.com...
>> W K wrote:
>> >
>> >
>> >> > If you don't replenish that, you won't be doing much exercise.
>> >
>> > ... which is that. Anything positive to say on that one? Its a key point to what makes a
>> > practical difference to cyclists. The comment "Energy adsorption is maximal in the 30-60
>> > minutes after exercise" , will be replenished sooner or later, and its better that it should be
>> > sooner if you want to do any more cycling in the near future.
>>
>> He only said that eating after execise was not a good way to lose weight, because the food will
>> be absorbed quickly. If you're an endurence athlete, then eating to replenish ASAP is a good
>> thing, if you're a bloater looking to maximise weight loss without feeling hungry, it's bad.
>
> He didn't actually mention whether this was food in general (something I've not really seen
> anything about), or for the building up of glycogen (standard sport physiology).

Doesn't matter. If you cycle to work, and then eat to replace what you've burned off, and then have
lunch, you lose weight much more slowely, if at all, than if you missed out the energy replacement
snack and just had lunch several hour later as normal. Whether or not you have the snack, you'll
feel just as hungry come lunch time.

Eating in the short time after excersize is only useful if you are going to excercise again in a
short period of time.

So - immediate energy replacement: good for sports people, bad for weight loss.

Here was me thinking that if you ate a small something, e.g. an apple, in-between meals, it speeded up your metabolism and made you burn lard more effectively.

I agree that eating right after exercise will lead to you absorbing whatever is in what you ate, I guess this is why bodybuilders work out and then go and chug a half-gallon of protein-fortified skimmed milk before eating 6 whole chicken breasts.

For me though, I lift weights during my lunch hour at work and then eat a tuna sandwich. After cycling I generally just consume plenty of fluids, I don't feel like eating for at least 3-4 hours aftwards. I could do with losing a few pounds though, so this thread has proven really interesting (even though it did start out talking about heart rate monitors and has metamorphosed into a diet discussion )

"Simian" <Simian@in_valid.semi-evolved.org> wrote in message
news:103u25upfubk6db@news.supernews.com...
> W K wrote:

> > He didn't actually mention whether this was food in general (something
I've
> > not really seen anything about), or for the building up of glycogen (standard sport physiology).
>
> Doesn't matter.
??!??!
> If you cycle to work, and then eat to replace what you've burned off, and then have lunch, you
> lose weight much more slowely, if at all, than if you missed out the energy replacement snack and
> just had
lunch
> several hour later as normal. Whether or not you have the snack, you'll feel just as hungry come
> lunch time.
>
> Eating in the short time after excersize is only useful if you are going
to
> excercise again in a short period of time.
>
> So - immediate energy replacement: good for sports people, bad for weight
loss.

You seem to have a fundamentally flawed view on this. There is a real difference between fat storage
and glycogen stores. All the above you have written seems to assume that there is no difference.

You have snipped and ignored the whole _scientific_ basis for the point I am making. Can you clarify
anything on my main point there, ie how true, false or intermediate the following is:

" losing your glycogen will be followed up by losing your fat."

On Wed, 25 Feb 2004 17:50:48 +0000 (UTC), cam@holyrood.ed.ac.uk (Chris
Malcolm) wrote (more or less):

>"Gearid Laoi/Garry Lee" <glee@iol.ie> writes:
>
>>ANY exercise will burn fat. Twirling effortlessly will burn fat. The rate at which it burns it is
>>another matter.
>
>>People who walk fast think that they burn more fat per mile. They don't. They just burn it faster.
>
>That might be true on wheels. It's certainly not true of walking on legs, which have to be
>accelerated and decelerated for every step.

The legs don't come to a standing stop with each step - only the /feet/ do.

And the centre of mass of the walker maintains a pretty even speed at all times.

Cheers, Euan Gawnsoft: http://www.gawnsoft.co.sr Symbian/Epoc wiki: http://html.dnsalias.net:1122
Smalltalk links (harvested from comp.lang.smalltalk) http://html.dnsalias.net/gawnsoft/smalltalk

W K wrote:
> Can you clarify anything on my main point there, ie how true, false or intermediate the
> following is:
>
> " losing your glycogen will be followed up by losing your fat."

Jeeze - it's neither true nor false, it depends what else you do.

Assuming you are at a steady weight:

If you lose glycogen through extra excersize, and then eat carbohydrate to replace it, and then eat
as (non extra glycogen loss) normal, there will be no loss of fat.

If you do not eat more carbohydrate to replace it, you will lose fat, because the body will have no
choice but to use fat for power.

Assuming you are a reasonably normal person, if you eat to replace, and you do it shortly after the
excersize, then you will feel just as hungry come normal mealtime.

Thus "eating shortly after excersize is an excellent way to put on what you have just lost".