A Snow and ski forum. SkiBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » SkiBanter forum » Skiing Newsgroups » Nordic Skiing
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Carbo Feeds When Training?



 
 
Thread Tools Display Modes
  #1  
Old December 10th 03, 12:46 AM
Gary Jacobson
external usenet poster
 
Posts: n/a
Default Carbo Feeds When Training?

A buddy of mine who is a monster endurance athlete used to tell me he
"intuitively" knew that feeding with carbohydrates when training prevented
best use of fat for metabolism and trained the body to need carbohydrate.
This was about 15 years ago.

I just read a summary of a study by Bengt Saltin, said to be a leading
sports physician. My buddy's contention is apparently supported. Here's the
blurb from http://www.jenex.com/news/index.html.:

One of the world's foremost Sports Medicine doctors, Bengt Saltin, who won
the IOC Sports Medicine prize in 2002 suspected that training for endurance
while using "sports drinks" and power bars might not the best way to develop
the body for optimal results in long distance races. ( Of course the sports
drinks power bar companies will try to prove him wrong. A well recognized US
Researcher told me that the difference between studies in Scandinavia and
the US is that in the States many studies are biased because major food and
soft drink firms sponsor the studies. The purse strings for sports research
in the US are mainly the marketing giants and without the money, no
research. In Scandinavia, Universities generally fund the studies. About ten
years ago I was indirectly involved with a University study on an exercise
product. The manufacturer of the product was convinced the device was an
exercise marvel and wanted a University study to back their marketing
claims. When the study showed that power walking was more beneficial than
their exercise device, the study was not allowed to be presented. The Doctor
who performed the study was obviously upset, but the study was funded by the
company and he was not allowed to publish it. )

It is well documented that you need maximum carbohydrate loading for long
distance races, but what if the body was better able to use both sugar and
fat for fuel? Most endurance athletes train using the same sports drinks as
when racing. However, Professor Saltin said that a few years ago he began to
question this method for training. Since we have more fat deposits for
energy than sugar it is important to be able to utilize both energy sources
optimally in long distance races. Bengt Saltin suspected that if we train
while consuming sugar drinks, the body would have fewer fat burning enzymes.
With sugar available, the enzymes are not needed so they don't get
developed.

Bengt first tested his theory at the University in Copenhagen, then a study
was made in Sweden on 18 skiers divided into two groups of nine. In the ski
study, which lasted for eight weeks, the two groups trained three times a
week for 1.5 hours and on the fourth day for approximately three hours. One
group used a well known sports drink while the others drank only water while
training and did not take any carbohydrates for at least one hour after
training. Prior to the experiment, biopsies were taken on all athletes.
After the eight weeks, new biopsies showed that the group that used only
water had substantially more important enzymes for the burning of fat. So in
race conditions, the water consuming group could better utilize the two
available fuel sources, sugar and fat. This month Bengt Saltin is starting a
third study of the potential benefits of reduced carbohydrate intake while
training for endurance races.

Gary (Got Hammer Gel?) Jacobson
Rosendale, NY



Ads
  #2  
Old December 10th 03, 04:19 AM
J999w
external usenet poster
 
Posts: n/a
Default Carbo Feeds When Training?

You're suggesting that it may not be in our best interest to drink blueberry
juice while skiing ??

Blasphemy !

:^]

jw
milwaukee
  #3  
Old December 10th 03, 12:13 PM
John Forrest Tomlinson
external usenet poster
 
Posts: n/a
Default Carbo Feeds When Training?

On Wed, 10 Dec 2003 00:46:05 GMT, "Gary Jacobson"
After the eight weeks, new biopsies showed that the group that used

only
water had substantially more important enzymes for the burning of

fat. So in
race conditions, the water consuming group could better utilize the

two
available fuel sources, sugar and fat.


These specific findings don't surprise me.

But the key question is, which was able to actually go faster? The
problem with training on no carbs or low carbs is that the quality of
training is reduced. It's hard to workout as intensely.

I think there is some value of not relying on sugar all the time in
training -- perhaps in certain types of workouts or certain times in
workouts (like early in endurance workouts) or even in certain periods
of training -- like in a base-building period. Or if trying to lose
weight. But if you're not keeping the stores of carbohydrate in your
body topped off, you're going to have a hard time training intensely.
Which is bad.

JT
  #4  
Old December 10th 03, 04:04 PM
external usenet poster
 
Posts: n/a
Default Carbo Feeds When Training?

To follow up JT's remarks, presumably it would be only during long-distance
endurance training that one should forgo using carb drinks and gels etc.,
not during any long race obviously, or during intensity training. The
question might be how long if at all after the endurance training before
you're 'allowed' to start stuffing yourself with pasta, or whatever.
Clearly a bad idea to say 'never', or you'd be too weak for any intense
training. Did the study have some control over what the athletes who
didn't take sportsdrinks did in the hour or two after finishing?

Best, Peter




  #5  
Old December 10th 03, 04:45 PM
Torsten Heycke
external usenet poster
 
Posts: n/a
Default Carbo Feeds When Training?

Funny, I just yesterday sent an email to an exercise physiologist
about this very topic. Several years ago a coach at Silverstar
admonished me for drinking Gatorade on an LSD ski, saying that it
predisposed me to using carbohydrate as fuel rather than fat. Everyone
I subsequently asked about this gave me a blank stare.

Whether that is true or not, I have another question: do we care about
using fat for energy for races at which we are almost immediately
racing at lactate threshold or higher?

Background:
Exercise physiologists use various measurements to determine lactate
threshold. One of those measurements is the Respiratory Exchange Ratio
(RER) which is apparently a good indicator of fuel utilization. RER is
the volume of Co2 divided by the volume of O2. We ventilate off
different percentages of O2 and Co2 which indicate whether we are
using carbohydrate vs fat for fuel. During a stress test, as we
approach lactate threshold we increasingly use carbohydrate. Over LT,
we are using almost all carbohydrate.

So, in races where you are operating at LT or greater, do we even care
if our body is predisposed to carbohydrate metabolism, since that is
what we're using anyway? Or is there still some small amount of fat
utilization going on, any bit of which we want to hang on to?

Obviously, for some folks racing 30-50km races, the research might be
very relevant since you might be racing at lower than LT and your
carbohydrate stores will presumably not last the entire race: you want
your body predisposed to using fat whenever it can.

I looked up the research by Bengt Saltin (you can too at
http://www.ncbi.nlm.nih.gov/entrez). I believe it is this article:

Glucose ingestion blunts hormone-sensitive lipase activity in
contracting human skeletal muscle.
Am J Physiol Endocrinol Metab. 2004 Jan;286(1):E144-50. Epub 2003 Sep
23


Torsten

"Gary Jacobson" wrote in message ...
A buddy of mine who is a monster endurance athlete used to tell me he
"intuitively" knew that feeding with carbohydrates when training prevented
best use of fat for metabolism and trained the body to need carbohydrate.
This was about 15 years ago.

I just read a summary of a study by Bengt Saltin, said to be a leading
sports physician. My buddy's contention is apparently supported. Here's the
blurb from http://www.jenex.com/news/index.html.:

One of the world's foremost Sports Medicine doctors, Bengt Saltin, who won
the IOC Sports Medicine prize in 2002 suspected that training for endurance
while using "sports drinks" and power bars might not the best way to develop
the body for optimal results in long distance races. ( Of course the sports
drinks power bar companies will try to prove him wrong. A well recognized US
Researcher told me that the difference between studies in Scandinavia and
the US is that in the States many studies are biased because major food and
soft drink firms sponsor the studies. The purse strings for sports research
in the US are mainly the marketing giants and without the money, no
research. In Scandinavia, Universities generally fund the studies. About ten
years ago I was indirectly involved with a University study on an exercise
product. The manufacturer of the product was convinced the device was an
exercise marvel and wanted a University study to back their marketing
claims. When the study showed that power walking was more beneficial than
their exercise device, the study was not allowed to be presented. The Doctor
who performed the study was obviously upset, but the study was funded by the
company and he was not allowed to publish it. )

It is well documented that you need maximum carbohydrate loading for long
distance races, but what if the body was better able to use both sugar and
fat for fuel? Most endurance athletes train using the same sports drinks as
when racing. However, Professor Saltin said that a few years ago he began to
question this method for training. Since we have more fat deposits for
energy than sugar it is important to be able to utilize both energy sources
optimally in long distance races. Bengt Saltin suspected that if we train
while consuming sugar drinks, the body would have fewer fat burning enzymes.
With sugar available, the enzymes are not needed so they don't get
developed.

Bengt first tested his theory at the University in Copenhagen, then a study
was made in Sweden on 18 skiers divided into two groups of nine. In the ski
study, which lasted for eight weeks, the two groups trained three times a
week for 1.5 hours and on the fourth day for approximately three hours. One
group used a well known sports drink while the others drank only water while
training and did not take any carbohydrates for at least one hour after
training. Prior to the experiment, biopsies were taken on all athletes.
After the eight weeks, new biopsies showed that the group that used only
water had substantially more important enzymes for the burning of fat. So in
race conditions, the water consuming group could better utilize the two
available fuel sources, sugar and fat. This month Bengt Saltin is starting a
third study of the potential benefits of reduced carbohydrate intake while
training for endurance races.

Gary (Got Hammer Gel?) Jacobson
Rosendale, NY

  #6  
Old December 10th 03, 09:44 PM
Rob Bradlee
external usenet poster
 
Posts: n/a
Default Carbo Feeds When Training?


Whether that is true or not, I have another question: do we care
about
using fat for energy for races at which we are almost immediately
racing at lactate threshold or higher?


Another question: Do we care about optimizing fat utilization if we
are able to consume carbs during races? If we had to race without
carbs then we might want to train without carbs. But we're able to
have the same sugary drinks and snacks during a race, maybe it's okay
to consume them in training. Or even beneficial because we train the
body to absorb the carbs while racing?

There does seems to be an idea here that the use of carbs makes us more
tired from the workout. That's what's interesting. But it sure sounds
like it needs a lot more research.

Rob Bradlee





  #7  
Old December 11th 03, 07:24 AM
Janne G
external usenet poster
 
Posts: n/a
Default Carbo Feeds When Training?

Torsten Heycke wrote:

Funny, I just yesterday sent an email to an exercise physiologist
about this very topic. Several years ago a coach at Silverstar
admonished me for drinking Gatorade on an LSD ski, saying that it
predisposed me to using carbohydrate as fuel rather than fat. Everyone
I subsequently asked about this gave me a blank stare.

Whether that is true or not, I have another question: do we care about
using fat for energy for races at which we are almost immediately
racing at lactate threshold or higher?


From the energy storage point of view it doesn't matter if your
race is under 1hour long (normal persons). But don't use fast carbos just
before a race so you alters the insulin balance, if not, then you start with
low bloodsugar (carbos in the blood) and have a hard time of doing anything
more strenuous for a while. When you are away and up to speed then you
can start using fast carbos because then your body regulates the bloodsugar
level due to the fact that it is consumed as energy by the working muscles
and is not stored.

Obviously, for some folks racing 30-50km races, the research might be
very relevant since you might be racing at lower than LT and your
carbohydrate stores will presumably not last the entire race: you want
your body predisposed to using fat whenever it can.


Precisely, but how many in this group just do 15k and shorter races and
have theire ultimate goal to make this short race the best of the seasoon?

For me, the shortest race is 40k, but i maybe do one 15k race a year.

--

Forward in all directions

Janne G
  #8  
Old December 11th 03, 07:36 AM
Janne G
external usenet poster
 
Posts: n/a
Default Carbo Feeds When Training?

Rob Bradlee wrote:

Whether that is true or not, I have another question: do we care
about
using fat for energy for races at which we are almost immediately
racing at lactate threshold or higher?


Another question: Do we care about optimizing fat utilization if we
are able to consume carbs during races? If we had to race without
carbs then we might want to train without carbs. But we're able to
have the same sugary drinks and snacks during a race, maybe it's okay
to consume them in training. Or even beneficial because we train the
body to absorb the carbs while racing?


Saltin had a discussion about this in a seminar that i have on my server
(in Swedish), he says that the amount of energy directly derived from the
digested food/sportsdrinks by it self can't sustain the bodys needs for more
than around 40-50% of Vo2Max. It was a nice thoght Rob but it seams that
we aren't equipped with that fast digestive system to support this to any
larger extent. The only thing we can do is to "blend" the storaged carbos
with digested carbos to some extent.

To make things worse, when approaching the Lactate Threshold (LT) the blood
starts to diverge from the digestive system to the working muscles to support
the high workload and this also lowers the output from it.

--

Forward in all directions

Janne G
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Thomas Alsgaard on training SBull10152 Nordic Skiing 0 December 3rd 03 04:21 AM
Are We Training Wrong? Jay Tegeder Nordic Skiing 19 October 24th 03 07:06 AM
Extreme training [ For inspiration: a true viking breaks a record] Jeff Potter Nordic Skiing 3 September 14th 03 09:15 AM
One pair for Racing, One Pair for training? Jim Farrell Nordic Skiing 2 September 8th 03 10:36 PM
LT Training for Lance, Why Not Nordic Skiers? Ken Roberts Nordic Skiing 4 August 18th 03 04:41 PM


All times are GMT. The time now is 03:46 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SkiBanter.
The comments are property of their posters.