Controversial article on hGH and Athletes - I bet not many of you will agree

[PHABIO]

TweetRecombinant Growth Hormone and the Athlete
by Nandi


In last month’s issue of Mind and Muscle (M&M #14) we looked at how growth hormone has been used in a number of trials to successfully induce weight loss in obese humans.

In order to better understand how GH affects this weight loss we also discussed in some detail how growth hormone and fat cells interact with one another. In this review of the existing literature, I would like to look at another growing use of recombinant GH: its use to increase athletic performance and increase muscle mass. There are much less data to guide us here than was available in our discussion of GH treatment of obesity. Further, the scientific literature contrasts starkly with the vast number of anecdotal reports of dramatic improvement in athletic performance and muscle mass seen with GH use. The scientific literature paints a rather bleak picture of recombinant GH as an ergogenic aid.

The positive results of some of the obesity trials discussed in Mind & Muscle #14 do suggest that GH might be beneficial to athletes and bodybuilders for weight loss while maintaining lean body mass. In fact, the studies in which recombinant GH has been administered to athletes and healthy young adults have yielded mixed results in terms of changes in strength and body composition, with the data often being difficult to interpret. This will be evident upon looking in detail at the research. For example, Yarasheski et al (1) looked at the effect of 14 days of recombinant GH administration (40 mcg/kg/day) on muscle protein synthesis rates in experienced weight lifters. The authors concluded that short-term GH administration neither increased the fractional rate of skeletal muscle protein synthesis nor did it reduce the rate of whole body protein breakdown despite significantly elevated levels of circulating IGF-1. This is in contrast to research that has shown that GH administration in normal, healthy humans in the postabsorptive state increases net muscle amino acid balance during the period of GH infusion (2). This anabolic effect is evidently short lived, since as mentioned, long-term studies show no increase in muscle mass. Note that in the study by Yarasheski et al protein synthesis/breakdown rates were measured several hours after the last GH injection, not during an infusion as in (2). Nevertheless, IGF-1 levels were still elevated 2 fold above baseline when Yarasheski et al collected their data.

As an aside, in another interesting study (3) that looked at the short-term infusion of a combination of GH and insulin, GH once again appeared to increase protein synthesis, but it also blunted the normal antiproteolytic effects of insulin.

Yarasheski et al (4) conducted another study in which GH was administered to healthy young men in conjunction with a resistance training program. The authors measured a number of parameters: change in body composition; muscle strength improvement; whole body protein turnover; and fractional muscle protein synthesis rate. Compared to placebo, the GH treated group showed a significantly larger increase in fat free mass. However, due to the rapid gain in this mass and the rapid loss after treatment ended, the authors attributed this gain primarily to water retention. There was no difference in strength gains between the GH and placebo treated groups. The GH treated group showed an increase in whole body protein synthesis but no change in fractional skeletal muscle synthesis rate. From this, and the lack of strength gains and muscle circumference, the authors deduce that the net protein accretion was not in the form of skeletal muscle.

Deyssig et al (5) conducted a similar study in trained power athletes. One group was given rhGH at 0.09 U/kgBW day while another was given placebo. Both groups participated in a resistance training program for six weeks. At the end of the study period changes in strength and body composition were measured in both groups. Again there was no difference between the two groups in the parameters measured. The authors concluded that GH treatment had no effect on strength or body composition in highly trained strength athletes.

Crist et al (6) examined the effects of six weeks of rhGH administration (30 – 50 mcg/kg, 3 days per week) in a group of young, highly conditioned (resistance and aerobic trained) men and women. FFM increased more (2.7 kg) and body fat decreased more (1.5 kg) during the GH treatment period than during the six-week placebo treatment period. It is unclear however whether the increase in FFM was due to any accumulation of skeletal muscle (contractile) protein. The study did demonstrate a greater fat loss during the GH period. This is consistent with some of the research presented last issue of M&M showing that GH treatment is capable of promoting fat loss.

In bodybuilders wishing to lower their body fat levels to what is humanly feasible, GH may be a viable option if one is willing to accept the possibility of some unhealthful side effects. In competitive endurance or strength athletes, as opposed to bodybuilders, the detrimental effects of GH use on performance may argue against its use. In a review of the topic (7) Rennie cites recent research conducted at the Danish Institute of Sports Medicine where GH administration to trained athletes actually impaired their performance (8). In these studies healthy endurance trained athletes were unable to complete accustomed cycling tasks after administration of exogenous hGH. The authors suggest that this could be a result of an observed increase in plasma lactate in the GH group compared to placebo. The significantly elevated lactate could result from the inhibition of the enzyme pyruvate dehydrogenase (PDH) by high levels of fatty acids released during GH-stimulated lipolysis. With PDH thus inhibited, pyruvate, produced from the glycolysis of glucose, is unable to enter the mitochondrial citric acid cycle and accumulates instead as lactate. One problem with this theory however, is that despite the increase in plasma free fatty acids observed by the authors, there was no apparent increase in lipid oxidation. The latter would be expected to be required to inhibit PDH. In any case, by whatever mechanism, GH administration clearly adversely affected cycling performance in this experiment.

Although the research described above looked at the acute effects of GH administration on athletic performance, there are chronic effects as well that could be detrimental to the athlete. Insulin resistance is a common side effect of GH use and would be expected to reduce glucose availability to muscle. GH administration also results in the impairment of muscle and liver glycogen storage. These latter effects, limited liver and muscle glycogen storage, could have a serious impact on recovery from strenuous exercise, as well as negatively impact performance itself as a result of decreased glycogen availability. The edema associated with GH administration could also impair athletic performance, as might the arthralgia experienced by many GH users. Rennie even cites the possibility that the fatty acidemia resulting from GH-induced lipolysis could promote cardiac arrhythmia during intense exercise. Although remarks such as this are reminiscent of some of the hyperbole from the medical community regarding anabolic steroids, there is probably some degree of legitimacy to the concerns of Rennie and others who have stressed the potential seriousness of GH related side effects. Athletes should at least be aware that concern exists over such things as potentially fatal as arrhythmia.

In addition to the potentially detrimental derangements in glucose metabolism mentioned above, GH administration in humans has been shown to induce a shift in muscle fiber type from type 2a to 2x (9, 10). The latter has been characterized as the “default” fiber type since the proportion of 2x fibers to type1 and type 2a is relatively high in “couch potatoes” compared to strength and power athletes. Resistance training induces a shift in the opposite direction from type 2x to 2a. During detraining, the muscle fiber type shifts back to 2x. The training induced shift is interpreted as an adaptive mechanism to the increased demands placed upon the muscle. If GH administration induces a shift in muscle fiber type away from the trained state, this could have negative implications for strength and power athletes.

Why, in light of all this negative evidence for any strength or muscle mass increase resulting from exogenous GH, is the bodybuilding literature replete with anecdotal reports of impressive gains in muscle mass and strength? And what motivates athletes to use GH in light of the negative research and side effects? One obvious possibility is that the research results are wrong or incomplete. But assuming they are not for the sake of furthering the discussion, another conceivable explanation for the reported gains in muscle mass are the lipolytic effects of GH discussed above. Bodybuilders could easily be mistaking enhanced definition for an increase in muscle. GH associated water retention could also add to the feeling that mass has increased. Certain anabolic steroids such as Dianabol and Deca Durabolin are notorious for causing water retention. These same drugs also have a reputation for increasing the resistance exercise induced muscle “pump”, contributing to a feeling of increased strength. The water retention from exogenous GH could have the same effect. Additionally, athletes and even researchers have noted that in elite athletes, studies would probably be unable to detect with statistical significance a 1 or 2 percent increase in performance that could result from GH use, and would make all the difference in the world to an elite athlete. Arguing against this is the observation that performances in a number of Olympic events such as shotput, discus, and javelin, particularly among women, have deteriorated since routine testing for anabolic steroids was implemented. It is very likely that these athletes who formerly were heavy users of anabolic steroids are now using rhGH, but it does not seem to be helping their performance. And perhaps the most obvious reason that many athletes and bodybuilders use GH is that the competition is using it.

In summary, despite numerous anecdotal reports to the contrary, to quote from (7),


The results of studies of muscle protein synthesis, body composition, and strength in healthy young to middle aged humans tell a different tale: so far no robust, credible study has been able to show clear effects of either medium to long term rhGH administration, alone or in combination with a variety of training protocols or anabolic steroids, on muscle protein synthesis, mass or strength.

These results, coupled with the possibility that GH use could significantly compromise training and performance, as described in (8), make a fairly strong argument against the use of GH in sport.



References

(1) Yarasheski KE, Zachweija JJ, Angelopoulos TJ, Bier DM Short-term growth hormone treatment does not increase muscle protein synthesis in experienced weight lifters. J Appl Physiol. 1993 Jun;74(6):3073-6.

(2) Fryburg DA, Gelfand RA, Barrett EJ. Growth hormone acutely stimulates forearm muscle protein synthesis in normal humans. Am J Physiol. 1991 Mar;260(3 Pt 1):E499-504

(3) Fryburg DA, Louard RJ, Gerow KE, Gelfand RA, Barrett EJ. Growth hormone stimulates skeletal muscle protein synthesis and antagonizes insulin's antiproteolytic action in humans. Diabetes. 1992 Apr;41(4):424-9

(4) Yarasheski KE, Campbell JA, Smith K, Rennie MJ, Holloszy JO, Bier DM. Effect of growth hormone and resistance exercise on muscle growth in young men. Am J Physiol. 1992 Mar;262(3 Pt 1):E261-7

(5) Deyssig R, Frisch H, Blum WF, Waldhor T. Effect of growth hormone treatment on hormonal parameters, body composition and strength in athletes. Acta Endocrinol (Copenh). 1993 Apr;128(4):313-8.

(6) Crist DM, Peake GT, Egan PA, Waters DL. Body composition response to exogenous GH during training in highly conditioned adults. J Appl Physiol. 1988 Aug;65(2):579-84.

(7) Rennie MJ.Claims for the anabolic effects of growth hormone: a case of the emperor's new clothes? Br J Sports Med. 2003 Apr;37(2):100-5.

(8) Lange KH, Larsson B, Flyvbjerg A, Dall R, Bennekou M, Rasmussen MH, Orskov H, Kjaer M. Acute growth hormone administration causes exaggerated increases in plasma lactate and glycerol during moderate to high intensity bicycling in trained young men. J Clin Endocrinol Metab. 2002 Nov;87(11):4966-75.

(9) Hennessey JV, Chromiak JA, DellaVentura S, Reinert SE, Puhl J, Kiel DP, Rosen CJ, Vandenburgh H, MacLean DB. Growth hormone administration and exercise effects on muscle fiber type and diameter in moderately frail older people. J Am Geriatr Soc. 2001 Jul;49(7):852-8.

(10) Lange KH, Andersen JL, Beyer N, Isaksson F, Larsson B, Rasmussen MH, Juul A, Bulow J, Kjaer M. 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. 2002 Feb;87(2):513-23

[orion76]

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Why, in light of all this negative evidence for any strength or muscle mass increase resulting from exogenous GH, is the bodybuilding literature replete with anecdotal reports of impressive gains in muscle mass and strength? And what motivates athletes to use GH in light of the negative research and side effects? One obvious possibility is that the research results are wrong or incomplete. But assuming they are not for the sake of furthering the discussion, another conceivable explanation for the reported gains in muscle mass are the lipolytic effects of GH discussed above. Bodybuilders could easily be mistaking enhanced definition for an increase in muscle. GH associated water retention could also add to the feeling that mass has increased. Certain anabolic steroids such as Dianabol and Deca Durabolin are notorious for causing water retention. These same drugs also have a reputation for increasing the resistance exercise induced muscle “pump”, contributing to a feeling of increased strength. The water retention from exogenous GH could have the same effect. Additionally, athletes and even researchers have noted that in elite athletes, studies would probably be unable to detect with statistical significance a 1 or 2 percent increase in performance that could result from GH use, and would make all the difference in the world to an elite athlete. Arguing against this is the observation that performances in a number of Olympic events such as shotput, discus, and javelin, particularly among women, have deteriorated since routine testing for anabolic steroids was implemented. It is very likely that these athletes who formerly were heavy users of anabolic steroids are now using rhGH, but it does not seem to be helping their performance. And perhaps the most obvious reason that many athletes and bodybuilders use GH is that the competition is using it.

The person who wrote this paragraph is simply second guessing and doesn't have a fucking clue what he's talking about.

I especially like this part:

Bodybuilders could easily be mistaking enhanced definition for an increase in muscle. GH associated water retention could also add to the feeling that mass has increased.

So bodybuilders mistakingly think GH is beneficial because it makes them look defined while the water bloat appears to add extra mass at the same time?? Talk about a contradiction!

[PHABIO]

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Originally posted by PHABIO

Deyssig et al (5) conducted a similar study in trained power athletes. One group was given rhGH at 0.09 U/kgBW day while another was given placebo. Both groups participated in a resistance training program for six weeks. At the end of the study period changes in strength and body composition were measured in both groups. Again there was no difference between the two groups in the parameters measured. The authors concluded that GH treatment had no effect on strength or body composition in highly trained strength athletes.


In a review of the topic (7) Rennie cites recent research conducted at the Danish Institute of Sports Medicine where GH administration to trained athletes actually impaired their performance (8).

Man, that's depressing!

[trip]

TweetWell, not surpising to me, and somewhat agree, did extensive research before I did my cycle and the studies on this stuff for performance athletes is almost nill. All the adds you see are in refrence to the wonders of gh are sedentary folks over 60 tha get great reuslts, well of course you should.

In a trained athlete depending on goals like all else risk rewards.

Does it work in bb, you bet.

My own experience, water retention and insulin resistance set in after 3 months, first 3 months great, after that pain in the ass for me.

Will I do more, yeah, down the road, cause no doubt it has benefits, not neccesarily all good though.

[PHABIO]

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Originally posted by trip
it has benefits, not neccesarily all good though.

I thought benefits are supposed to be all good!
(j.k., thanks for the answer trip)

But seriously, why is it that with almost any drug you'll find ten different results of ten different studies, some even going as far as contradicting themselves?

[JohnnyB]

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Originally posted by PHABIO
Man, that's depressing!

It takes more then 6 weeks to see results from HGH

JohnnyB

[jsjs24]

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Originally posted by JohnnyB
It takes more then 6 weeks to see results from HGH

JohnnyB

And you need to stack aas with it.

[JohnnyB]

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Originally posted by orion76


I especially like this part:



So bodybuilders mistakingly think GH is beneficial because it makes them look defined while the water bloat appears to add extra mass at the same time?? Talk about a contradiction!

I believe he's talking about 2 different effects that can be mistaken for added mass. Low dose HGH can cause fat loss which could be interpreted as a lean mass gains because of the definition. High dose HGH can cause water retention which could be interpreted as mass gains.

Nandi12 is a very knowledgeable Bro, he does read lots of study, of which some he posts or uses in articles he writes. Some of his stuff can be over whelming, this is not one of his best that's for sure.

JohnnyB

[orion76]

TweetThanks Johnny, I wasn't familiar with Nandi.

I'm sure he writes great articles but this is not one of them

[AnotherUser]

TweetI'll 2nd that Nandi is a really smart guy. Probably one of the smartest on the boards (he's on cuttingedgemuscle.com by the way). I know he holds an M.S. degree, not sure what in though...

[JohnnyB]

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Originally posted by orion76
Thanks Johnny, I wasn't familiar with Nandi.

I'm sure he writes great articles but this is not one of them

I agree it wasn't his best, it didn't even seem like him. Goes to show wee can all have off days.

JohnnyB