Study shows arginine reduces post-exercise release of growth hormone

[sonicology]

I saw this on ImmInst, thought it might be of interest to people here.

Oral arginine does not stimulate basal or augment exercise-induced GH secretion in either young or old adults.

* Marcell TJ,
* Taaffe DR,
* Hawkins SA,
* Tarpenning KM,
* Pyka G,
* Kohlmeier L,
* Wiswell RA,
* Marcus R.

Department of Exercise Science, University of Southern California, Los Angeles, USA. marcellt@grc.nia.nih.gov

BACKGROUND: Growth hormone (GH) helps maintain body composition and metabolism in adults. However, basal and peak GH decline with age. Exercise produces a physiologic GH response that is subnormal in elderly people. Arginine (Arg) infusion can augment GH secretion, but the efficacy of oral Arg to improve GH response to exercise has not been explored. We investigated whether oral Arg increases GH secretion in young and old people at rest and during exercise. METHODS: Twenty young (Y: 22.1 +/- 0.9 y; SEM) and 8 old (O: 68.5 +/- 2.1 y) male and female subjects underwent three different trials following determination of their one-repetition maximum strength (1-RM); exercise only (EO; 3 sets, 8-10 reps at 85% of 1-RM; on 12 separate resistive lifts), Arg only (5.0 g), or Arg + exercise. Blood samples were collected between successive lifts, and GH (ng x ml(-1)) was determined via RIA. RESULTS: In Y vs O: Basal GH secreted (area under the curve) was 543.6 +/- 84.0 vs 211.5 +/- 63.0. During EO, values were 986.6 +/- 156.6 and 517.8 +/- 85.5. Both were significantly lower in the older individuals (p < .05). Oral Arg alone did not result in any increase in GH secretion at rest (310.8 +/- 73.2 vs 262.9 +/- 141.2). When Arg was coadministered during exercise, GH release was not affected in either the young or old and appeared to be blunted in the young compared to the exercise only trial in the young. CONCLUSION: Based upon these findings, we concluded that oral Arg does not stimulate GH secretion and may impair GH release during resistive exercise.

I have to admit this surprised me as I had been led to believe that arginine raised GH levels, not lowered. Comments?

[sonicology]

Nobody have any opinions on this?

Everyweek we get several threads asking what is the best NO/arginine type product, I would have thought there would be some interest to hear it could be harming your gains?

[Skigazzi]

I posted it here a while back, but its definitley a good re-post.

I never really understood the real point to an NO product, and this makes me scratch my head even more.


Perhaps taking it a couple times a day away from a workout would give small gh releases, but probably nothing worth your trouble.

[RhodeyzFinest]

doesnt it blunt GH pre workout ?

[GeneGnomeX]

There are a couple other methods which arginine could work but since everything points to no muscle mass increase they are irrelevant. Only time arginine should be used is during periods of illness, unless you believe that myofibrilar hydration from the pump will build more muscle but currently signs point to no.

Volume 18, Issue 7, Pages 657-661 (July 2002)



View previous. 24 of 42 View next.

Use of amino acids as growth hormone-releasing agents by athletes

Joseph A. Chromiak PhD Corresponding Author Information Send E-mail to Author*a and Jose Antonio PhDb

Abstract
Specific amino acids, such as arginine, lysine and ornithine, can stimulate growth hormone (GH) release when infused intravenously or administered orally. Many individuals consume amino acids before strength training workouts, believing this practice accentuates the exercise-induced GH release, thereby promoting greater gains in muscle mass and strength. The GH response to amino acid administration has a high degree of interindividual variability and may be altered by training status, sex, age, and diet. Although parenteral administration consistently leads to increased circulating GH concentration, oral doses that are great enough to induce significant GH release are likely to cause stomach discomfort and diarrhea. During exercise, intensity is a major determinant of GH release. Although one study showed that arginine infusion can heighten the GH response to exercise, no studies found that pre-exercise oral amino acid supplementation augments GH release. Further, no appropriately conducted scientific studies found that oral supplementation with amino acids, which are capable of inducing GH release, before strength training increases muscle mass and strength to a greater extent than strength training alone. The use of specific amino acids to stimulate GH release by athletes is not recommended.

Keywords: resistance exercise, strength training, muscle, arginine, lysine, ornithine

[SF_Muscle_]

Arginine/Ornithene failed miserably at GH raising properties in earlier years. I thought everyone already knew that.

[Sho-stopper]

I saw this on ImmInst, thought it might be of interest to people here.



I have to admit this surprised me as I had been led to believe that arginine raised GH levels, not lowered. Comments?

Well...I'm not trying to say if this is true, or false. I wouldn't put much stock in this study however. They had such a small sample size with 28 people, hardly enough to come to a real conclusion. It also didn't say how long they followed the study group. From reading it it seemed like it was more of a "here take this and we'll take some blood samples", but of course I'm just reading the excerpt that was posted. If arginine can in fact raise GH levels I would imagine it would take quite a while to see results. Another point I have is that in what studies I have seen, they were using IV arginine as opposed to po (by mouth), and from what I remember there was no comparison as far as the potency and efficacy of IV Arginine compared to oral Argine which the above study used.

Really the only reason I use NO products is because I like how swole my veins get...and I suppose because I've read that it promotes overall vascular health.

[UpstateTank]

I dont buy it

In the most recent Fitness Rx Magazine...Pg. 38
"Arginine Not as Good Before Weight Training"

Growth Hormone is a proven fat figther and muscle builder and is popular with many weightlifters and aging adults. Unfortunately, daily injections of growth hormone are expensive and inconvenient. Many oral supplements sold on the Internet claim to increase growth hormone levels, but few scientific studies support their use. Researchers from Syracuse University found that combining arginine supplements with weight training increased blood hormone levels. Oral arginine, by itself, also increases growth hormone, but not as much as when it was combined with weight training. This study did not show that oral arginine supplements increased muscle size or strength, but it supported the effectiveness of oral growth hormone boosters. It's doubtful that boosting growth hormone with oral supplements is as effective as injected growth hormone. (Journal Applied Physiology, 101:848-852, 2006)