Growth Hormone Stimulates Collagen Synthesis, But Not Protein Synthesis

[HawaiianPride.]

More info concluding the idea behind GH in correlation with C.S.

By Robbie Durand, M.A.

Senior Science Editor

Growth Hormone Stimulates Collagen Synthesis, But Not Protein Synthesis

“GROWTH HORMONE IS NO MUSCLE BUILDER.” This headline appeared in many newspapers and newswires in the last few months. The controversy was based on a study that recently appeared on the science blogs— making news headlines. A recent meta-analysis (a collection of previous research findings) published in the Annals of Internal Medicine1 reported that growth hormone (GH) has little benefit for building muscle or improving quality of life. The article explained that while GH has been reported to build muscle and reduce body fat, the research does not support GH as a muscle builder. The meta-analysis also noted that GH causes a host of unhealthy side effects including joint pain, soft tissue swelling, carpal tunnel syndrome, and a heightened risk of diabetes.

The article did acknowledge that GH administration increased lean muscle mass by more than 2 kilograms (4 pounds), and decreased fat mass by roughly the same amount— but noted that the side effects associated with GH usage were not worth the small changes in body composition. The lead author also claimed that the small increases in lean mass could easily be accomplished by a heavy resistance exercise program; he basically stated you’re paying big bucks for a small investment in muscle growth. So is GH as worthless for building muscle as the media has claimed?

GH: Emperor’s New Clothing

If you are not familiar with the story of “The Emperor’s New Clothes,” it’s an interesting fable. An Emperor who only cares about his wardrobe hires swindlers who promise him the “grandest wardrobe he ever wore.” The tailors tell him the wardrobe consists of clothes made from a fabric that is invisible to anyone who is unfit for his position or “just hopelessly stupid.” The Emperor cannot see the clothes himself, but pretends that he can— for fear of appearing unfit for his position or stupid; his ministers do the same.

When the swindlers report that his suit is finished, the Emperor marches in procession before his subjects. A child in the crowd calls out that the Emperor is wearing nothing at all, and the cry is taken up by others. The Emperor cringes, suspecting the assertion is true, but holds himself up proudly and continues the procession. Much like the Emperor and his invisible clothing, bodybuilders are still taking GH— thinking it’s a muscle builder when in fact there is little evidence that GH can increase muscle mass.

Previous research has shown that GH administration has no effect on human muscle size and muscle protein synthesis.2 Other studies reported that GH did not stimulate muscle protein synthesis. 3,4,5,6 Interestingly, many athletes may “feel” like they are bigger while on GH— because of the perception of increased water retention and possibly increased muscle stiffness due to growth of collagen tissue. This month’s Journal of Physiology made my draw drop after I read their latest article on how GH affects muscle and collagen protein synthesis.

Growing Collagen, Not Muscle!

Researchers from Denmark performed a randomized, double-blinded, placebo-controlled crossover trial in which sedentary subjects were supplemented with recombinant human GH (rhGH) initially (1-7 days) at 33.3 μg kg per day, and at 50 μg kg per day for the latter half (8-14 days) of the experimental period. Subjects performed a bout of leg extension exercises, which consisted of 10 sets of 10 reps at 70 percent of their 1RM. Subjects returned to the laboratory and underwent markers of protein synthesis for tendon and muscle collagen proteins and muscle protein synthesis at 24 hours post-exercise.

At the end of the study, a corresponding increase in systemic IGF-1 and IGFBP-3 occurred with rhGH supplementation, whereas there were no changes in systemic GH or associated blood indices in the placebo condition. Tendon collagen I mRNA expression and tendon collagen protein synthesis increased by 3.9-fold and 1.3-fold, respectively, and muscle collagen I mRNA expression and muscle collagen protein synthesis increased by 2.3-fold and 5.8-fold, respectively.

Myofibrillar protein synthesis was unaffected by elevation of GH and IGF-1. So basically, GH increased serum IGF-1 levels; but there were increases in collagen and tendon protein synthesis, but no increase in muscle protein synthesis.7

The study found that circulating and local IGF-1 increased threefold, and there were no increases in muscle protein synthesis. This is great news for muscle strength athletes, given that stronger tendons and collagen are going to enhance muscle strength. GH did not do anything directly to muscle— unlike testosterone , which has direct effects of muscle protein synthesis rates.

Based on this study, GH/IGF-1supports the collagen framework around muscle fibers rather than the muscle contractile apparatus per se in adult skeletal muscle. GH/IGF-1 may be more biologically important for strengthening the supportive matrix in tissues than for muscle cell hypertrophy.

Thus, GH/IGF-1 may be important for tissue remodeling for traumatic musculoskeletal injuries in which collagen or tendons are injured. I am not saying that GH is not important, as many studies have reported that low GH is associated with reduced muscle mass and increased fat mass. However, I see little point in including GH in off-season cycles if you are trying to solely increase muscle mass for the price. On the other hand, maybe the increased collagen strength leads to more resistance that can be handled— which indirectly allows a heavier workload to be utilized and greater tension applied to the muscle— which indirectly, can increase muscle mass.



References:

1. Liu H, Bravata DM, Olkin I, Nayak S, Roberts B, Garber AM, Hoffman AR. Systematic review: the safety and efficacy of growth hormone in the healthy elderly. Ann Intern Med, 2007 Jan 16;146(2):104-15. Review.

2. Rennie MJ (2003). Claims for the anabolic effects of growth hormone: a case of the emperor’s new clothes? Br J Sports Med, 37, 100-105.

3. Liu H, Bravata DM, Olkin I, Friedlander A, Liu V, Roberts B et al. (2008). Systematic review: the effects of growth hormone on athletic performance. Ann Intern Med, 148, 747-758.

4. Yarasheski KE, Zachweija JJ, Angelopoulos TJ & Bier DM (1993). Short-term growth hormone treatment does not increase muscle protein synthesis in experienced weight lifters. J Appl Physiol, 74, 3073-3076.

5. Blackman MR, Sorkin JD, Munzer T, Bellantoni MF, Busby-Whitehead J, Stevens TE et al. (2002). Growth hormone and sex steroid administration in healthy aged women and men: a randomized controlled trial. JAMA, 288,2282-2292.

6. Lange KH, Andersen JL, Beyer N, Isaksson F, Larsson B, Rasmussen MH et al. (2002). GH administration changes myosin heavy chain isoforms in skeletal muscle but does not augment muscle strength or hypertrophy, either alone or combined with resistance exercise training in healthy elderly men. J Clin Endocrinol Metab, 87, 513-523.

7. Doessing S, Heinemeier KM, Holm L, Mackey AL, Schjerling P, Rennie M, Smith K, Reitelseder S, Kappelgaard AM, Rasmussen MH, Flyvbjerg A, Kjaer M. Growth hormone stimulates the collagen synthesis in human tendon and skeletal muscle without affecting myofibrillar protein synthesis. J Physiol, 2010 Jan 15;588(Pt 2):341-51.

[lovbyts]

I need a buddy of mine to read this (he wont). I have been saying that for years. He is educated in the medical field but he truly believe HGH is a HUGE muscle builder and Testosterone has NOTHING or very little to do with muscle growth...

[stevey_6t9]

the study showed results over a 2 week period.

how about one that shows over 6 months?

[lovbyts]

the study showed results over a 2 week period.

how about one that shows over 6 months?

I understand your point but I think most people here know HGH is not the muscle builder king by any means.

This is not saying it does not help increase muscle size and from what I remember it's due to actually increasing the number of muscle cells.

[NVR2BIG1]

Lets look at the facts here, competitors now are probably walking onstage with 50 lbs more mass than 30 yrs ago. Why?

[myturn]

from what i understand hgh increases the number of muscle cells as stated from above and when you combine with insulin it will mature smaller muscle cells any one care to comment on a long regimine of growth with out alot of aas taken

[warchild]

Lets look at the facts here, competitors now are probably walking onstage with 50 lbs more mass than 30 yrs ago. Why?

ditto

[Tennis_tom]

I dont think anyone was ever arguing that you could do 10 sets of leg extensions only on 2 weeks of HGH and expect to get results.

[antonioribera]

What is the best HGH to use, if any?

[DanB]

Any legit pharm grade, if you cant obtain that then dont waste your money

[yannick35]

Well GH will build mass serostim and acrtrotopin are both used in HIV positive people but the dosage is insane like 15-20IU per day. But it gets the job done. Great article for me because i am looking for maximum collagen synthetics since i want to repair my body.

Taking GH for muscle building or worst fat loss is a waste of money IMO diet and training will take care of both, and it will be a lot less expensive to do a steroid cycle. My body has changed since starting GH 6 or so weeks ago, but i did not gain any new muscles or anything. I do feel a lot better.
testosterone .

[MuscleInk]

the study showed results over a 2 week period.

how about one that shows over 6 months?

This is a problem with a lot of published science. I'm not bashing the empirical process, I'm an 18 year disciple of scientific research and have published in many peer reviewed journals but a lot of science is incremental in knowledge and limited to short term data collection.

The current publication nicely illustrates this. I'm not surprised to see some effects of GH over a short term but what about long term effects? The anti catabolic and (supposed) anabolic benefits of GH are purported with long term administration not short term usage. Moreover, optimal doses have still yet to be established. I have yet to see dose finding and MTD curves linking dose to effects. Like any drug, effects follow an inverted parabola - increasing doses lead to increased benefits however, at some dose, the risks exceed benefits and benefits decline with elevated doses (the inverted U effect).

The publication offers useful findings on mechanisms of GH during short term use but is far from a complete story and should be critiqued with these limitations in mind.

[DanB]

^^^^^^^

If you know anybody who needs subjects for a long term, high dose study then put my name forward

[MuscleInk]

^^^^^^^

If you know anybody who needs subjects for a long term, high dose study then put my name forward

Lol......we are planning one. Protocol is still being written and subject population planned. I'll keep you in mind for it. I've got a lot of interest in this as well. We want to see some long term data that could go 3-4 years out. An extension could be added for longer term data collection as well.

[DanB]

Ive always said I will be guinea pig for any and all sponsered studys with HGH and/or peps once there is a degree of safety to it and the compounds in question arent complete unknowns,

Matter if interest, who would fund a study like that because there would be substantial costs involved and I imagine that the manufactuers wouldnt play any part in funding for several reasons, first that springs to mind is because its an off label use and they cant benefit from it since they cant directly market it for BB purposes

[MuscleInk]

Our company is partnering with a US Pharma company for a new indication of use. Protocol will include target population and health controls using within subject design. Compounds will include comparison between hgh and igf-1.

[DanB]

Hmmmm interesting.....

[Rwy]

^^^^^^^

If you know anybody who needs subjects for a long term, high dose study then put my name forward

lol.........

[jseek]

Gotta love how ethical/moral review boards kill real studies. They'll approve a dose guaranteed to not do anything and say that drug doesn't work.
Interested in how high they consider a "high" dose

[Edwin23q]

Our company is partnering with a US Pharma company for a new indication of use. Protocol will include target population and health controls using within subject design. Compounds will include comparison between hgh and igf-1.

Hi, without intentionally wanting to bump 7 month old threads, I'm just wondering if the long term hgh testing has commenced as yet.

Sent from my iPhone using Forum Runner

[stl]

So this must help heal things like tendons?