Oral L-arginine before resistance exercise blunts growth hormone in strength trained

[HITFrank]

Oral L-arginine before resistance exercise blunts growth hormone in strength trained males. - PubMed - NCBI

Lots of PWO's contain Arginine of some sorts, counterproductive?

 

[VaughnTrue]

I am not a fan of arginine in pre-workouts. I'd always opt for agmatine, citrulline, and/or nitrates in its place.

 

[justhere4comm]

ncbi.nlm.nih dot gov/m/pubmed/20724562/?i=56&from=/24225560/related"

 

[HITFrank]

One of the chemists at Blackston Labs wrote this Guerillastyle:
"Almost every preworkout over the last 15 years have contained some form of Arginine. It was the original vasodilator and was in every "NO" product. We now have much better options for a pump. The researchers in the study found something that should confirm to supplement companies that Arginine shouldn't be used in preworkouts anymore. Trained athletes who ingested 6g of Arginine before working out had a 41% decrease in GH and IGF-1 levels postworkout. Your body naturally releases GH and other growth factors after a workout to help repair and rebuild muscle tissue. Taking Arginine before a workout may significantly hinder your body's natural anabolic response to training! With so many better options for pumps, including citrulline malate and my favorite, organic nitrates, arginine is outdated. In fact, citrulline has been shown to raise arginine(and thus NO) plasma levels greater than arginine."

Any truth to this?

 

[VaughnTrue]

yes, citrulline > arginine

 

[HIT4ME]

I think we over simplify things sometimes. I'm no expert, but we often like to think of things in terms of timing and what happens immediately after a workout, etc. It could be that arginine hinders the release of GH, or it could be that arginine alleviates some issue that means we require less GH to get the job done, or makes GH more effective. I'm not saying I'm right, just saying there are other possible answers to this.

Either way, arginine isn't the best pump enhancer as others have pointed out and if it concerns you, there are plenty of Pre-W without arginine in them. Of course, taking Citruline is a better way to increase your blood levels of Arginine than taking arginine itself...so not sure how citrulline wouldn't have the same effect.

 

[Rodja]

The GH and test release from training is insignificant in the big picture. GH is even less significant considering most consume carbs and protein post training.

 

[kbayne]

Been known for quite some time now regarding arginine and GH.

 

[justhere4comm]

The studies I saw were from fasted, but what about non fasted?

 

[Lynks8]

I wouldn't worry about it.

Yes, Arginine combined with exercise has been shown in multiple studies to attenuate GH response.

The theory as to why thus far seems to be that, since both Arginine supplementation and exercise stimulate GH release significantly, when combined they cause such a strong stimulus that autonegative feedback causes a refractory period which suppresses the somatotrope. This makes the following claim from the study in question very interesting to me: "Furthermore our data shows that the GH suppression was not due to a GH or IGF-1 induced autonegative feedback loop." I need to read the full text.

Anyway, the real question is, does it matter? I would tend to agree with Rodja that these short term GH fluctuations are largely unimportant for overall muscle building. I've yet to see convincing evidence that acute hormonal response to resistance training has any significant impact on hypertrophy.

p.s. I wouldn't say that Citrulline is necessarily the answer. since it metabolizes into Arginine. However, perhaps the process of being turned into Arginine slows the GH response to pure Arginine alone? Then again, this process must happen pretty rapidly, given how quickly Citrulline's vasodilating effects occur.

 

[HITFrank]

I wouldn't worry about it.

Yes, Arginine combined with exercise has been shown in multiple studies to attenuate GH response.

The theory as to why thus far seems to be that, since both Arginine supplementation and exercise stimulate GH release significantly, when combined they cause such a strong stimulus that autonegative feedback causes a refractory period which suppresses the somatotrope. This makes the following claim from the study in question very interesting to me: "Furthermore our data shows that the GH suppression was not due to a GH or IGF-1 induced autonegative feedback loop." I need to read the full text.

Anyway, the real question is, does it matter? I would tend to agree with Rodja that these short term GH fluctuations are largely unimportant for overall muscle building. I've yet to see convincing evidence that acute hormonal response to resistance training has any significant impact on hypertrophy.

p.s. I wouldn't say that Citrulline is necessarily the answer. since it metabolizes into Arginine. However, perhaps the process of being turned into Arginine slows the GH response to pure Arginine alone? Then again, this process must happen pretty rapidly, given how quickly Citrulline's vasodilating effects occur.

Great answer! Thanks!

My favourite PWO contains 3g Arginine Alpha Ketoglutarate (AAKG) so I was a little worried, don't want to take a PWO that feels great, but is counterproductive.

 

[ambulldog]

Oral arginine doesnt do anything. So many clinical studues backing that statement.

You want a pre workout that works? Clinical studies abound. Cialis, viagra etc.

They actually work, fir everyone. You dont need anecdotal **** from posters on any boards. They flat out get the job done