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hemants
09-02-2003, 06:43 AM
I got into this discussion with my bro in law who is a doctor and quickly realize that I didn't fully understand the mechanics.

What exactly is it that tells the body to lose muscle instead of burning fat for fuel?

bradley
09-02-2003, 09:11 AM
The short answer would be hormones.:)

There are various catabolic hormones in the body that will cause proteolysis (muscle catabolism), such as glucagon and cortisol. Glucagon, as I am sure you know, is the opposite of insulin, and will be secreted when blood sugar levels drop below baseline. The same way insulin is secreted when blood sugar levels increase above baseline.

Cortisol is secreted in response to stress, whether that stress be associated with exercise, missed meal, etc. Obviously there is much more to muscle catabolism than what I mentioned above and I do not claim to know all the mechanisms by which this can occur.:)

Here are a couple of abstracts that relate to cortisol and glucagon being catabolic, and there are plenty more stating the same.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6365973&dopt=Abstract

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8690809&dopt=Abstract
"We conclude that glucagon is the pivotal hormone in amino acid disposal during an AA load and, by reducing the availability of AA, glucagon inhibits protein synthesis stimulated by AA. These data provide further support for a catabolic role of glucagon at physiological concentrations."

hemants
09-02-2003, 09:29 AM
Hmmm. thanks.

So, a missed meal will result in cortisol? Glucagon? Both being secreted?

What hormones will determine whether it is fat or muscle that is used for fuel? (Or, if you will, what percentages of each are used?)

Thanks!

bradley
09-02-2003, 09:43 AM
Originally posted by hemants
So, a missed meal will result in cortisol? Glucagon? Both being secreted?

Just because you miss a meal does not necessarily mean that you will catabolize muscle tissue. If you were to go for extended periods of time without eating, then your body would consider this a type of "stress," at which time cortisol would be secreted.

Glucagon can be catabolic, but is is also used to mobilize glycogen and fat to raise blood sugar levels when they fall below baseline levels, as previously mentioned. Although glucagon can also cause amino acids to be converted to glucose as well, via gluconeogenesis. At what point this occurs I am unsure, but the catabolic effects of glucagon are decreased when an individual is following a ketogenic diet, due to the body's decreased glucose requirements.



What hormones will determine whether it is fat or muscle that is used for fuel? (Or, if you will, what percentages of each are used?)

There are other hormones that come into play as lipolysis is concerned, but yes glucagon is one of those hormones. Another group of hormones, catecholamines, will also be reponsible for increasing lipolysis.

As far as percentages I am unsure as to whether there is a definite answer. I think that you would be better off engaging in activites that will minimize the catabolic hormones, but with that being said you will undoubtedly experience some rise in these hormones, as far as exercise is concerned. This is one of the reasons that many people advocate short intense workout, and also one of the reasons that pre/post workout nutrition is so harped upon.

hemants
09-02-2003, 10:14 AM
Thanks. I guess the implicit message is that in small doses, glucagon/cortisol etc. present the body will result in a higher percentage of fat burning but that too much of a good thing is bad and the body will also catabolize more muscle tissue if the dose/duration is too high?

Agree?

bradley
09-02-2003, 04:06 PM
Originally posted by hemants
Thanks. I guess the implicit message is that in small doses, glucagon/cortisol etc. present the body will result in a higher percentage of fat burning but that too much of a good thing is bad and the body will also catabolize more muscle tissue if the dose/duration is too high?

Agree?

Yes, pretty much.:)

Both are going to be present at some point and to some degree, but the best approach is to try and use this to your advantage.

bradley
09-03-2003, 04:58 PM
Here are some things that I ran across concerning gluconeogenesis. Thought they might be of interest.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=371355&dopt=Abstract
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2058658&dopt=Abstract
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9101062&dopt=Abstract

Makaveli_786
09-08-2003, 08:35 AM
I think the simple answer is when you eat you get bigger... when you eat les its counterproductive(i know theres a lot more to it though)

Scott S
09-08-2003, 10:44 AM
If stress leads to a significant rise in catabolic hormones, have there been any studies showing benefits of meditation to athletes? This is interesting. :)

pusher
09-08-2003, 11:15 AM
Thats an interesting observation Scott. I imagine you would be hard pressed to find scientific studies quantifying the mind/body connection as in meditation. But I wonder if the benefits of focusing you mind on achieving your general goals is actually more important than any direct effect your mental state can have on the balance of hormones in your body. I bet most professional athletes are extremely 'focused' on their performance.

hemants
09-08-2003, 11:33 AM
Meditation has been shown to increase alpha wave activity which is more relaxing than sleep. And we all know that adequate rest is vital to bodybuilding.

I'm sure there is a limit to the benefit though.

And until you can package mediation into a pill and sell it no one is going to bother finding out :)

Scott S
09-08-2003, 11:37 PM
Well I'm gonna do it anyway, then. "Ommmmmm..." :D


Seriously, if I'm interpreting "stress" correctly, then perhaps people who worry all day might be shooting themselves in the foot, as opposed to someone who has learned to take things in stride. Or maybe it doesn't matter.

arjun
09-09-2003, 02:27 AM
Meditation is used widely in the martial arts community, especially with people training for combat or full contact tournaments.

Meditation raises focus, not just while you are doing it, but at all times. It brings stress levels down, and is scientifically proven to make you happier (we dont need this though, we have zoloft, prozac, wellbutrin, etc).

Related to martial arts it has made practitioners more alert of their opponents and surroundings, and keeps you from getting angry (This may sound silly, but you can get addrenaline from things other than anger, and anger in a tournament is not good. Many a people have gotten disqualified for getting pissed off after taking a solid hit and going a bit crazy).

Meditation is a tool for the mind, though the mind controls the body, and your mental state does effect your physical state. Does it have direct uses for training in hypertrophy? Probably not many, though it makes great improvements on your life in general, unless you consider being depressed and moody valuable assets in your personality.

Do it if you like, but dont expect it to take your training to a new level. The best and most recognized form of meditation is that practiced by buddhists. No, you dont have to be a monk to do it, you dont have to beleive in buddhism. In fact buddhist meditation doesnt have any religios requirements or practices interweaved within it.

You can find instruction and articles on buddhist meditation here:

http://www.buddhanet.net/ebooks_m.htm

Also: seed meditation is another popular and easy type of meditation, though it does not produce as great as results that buddhist or zen meditation does. I have no links for this practice because i dont believe it is really meditation and should be practiced as such.

If you want more general and direct instruction i can help out with personal experience and more resources if you contact me privately.

bradley
09-09-2003, 02:31 AM
Originally posted by Scott S
Well I'm gonna do it anyway, then. "Ommmmmm..." :D


Seriously, if I'm interpreting "stress" correctly, then perhaps people who worry all day might be shooting themselves in the foot, as opposed to someone who has learned to take things in stride. Or maybe it doesn't matter.

Stress has been linked to abdominal fat, which is due to the effects of elevated cortisol. These effects are usually seen with the accumalation of visceral adipose tissue.


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12119665&dopt=Abstract
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10889792&dopt=Abstract
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TB0-41H3KTD-J&_coverDate=10%2F31%2F2000&_alid=112063944&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=5128&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=49618632edfded3fb1eed375f49cc6ca

arjun
09-09-2003, 03:27 AM
I dont have time to go through those resources you posted yet, but is it also the mental factor, lol, stress being caused from insecurity or concern with body fat. No im joking.

Your saying that stress contributes to most of our countries population being nearly obese? And im sure obesity also causes stress.... its a vicious circle.

bradley
09-09-2003, 05:32 AM
Originally posted by arjun
Your saying that stress contributes to most of our countries population being nearly obese? And im sure obesity also causes stress.... its a vicious circle.

I am saying that stress is one of the factors associated with abdominal fat, but I think the main causes for obesity are overeating and lack of exercise.;)

Spawn
09-09-2003, 09:11 AM
i really didn't read every single post, just skimmed a little coz i have to go soon...but when you say "stress" would this include mental stress?? like, studying your butt-off, freaking out before a quiz kind of stress? or a physical kind (ie missed meals, as stated previously).

so it must be BAD when ur hungry, especially for someone who's supposed to be bulking isn't it??

sorry if these have already been answered..gotta run, later!

Relentless
09-09-2003, 09:18 AM
stress can be both and more, Spawn

physical stress
emotional stress
mental stress

all have effects on your physiology

Makaveli_786
09-18-2003, 11:55 AM
So can meditation be used to replace sleep?

I dont mean totally replace it but could you meditate for a while and sleep 6 hours instead of 8?