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West DW, Kujbida GW, Moore D, Atherton PJ, Burd NA, Padzik JP, Delisio M, Tang
JE, Parise G, Rennie MJ, Baker SK, Phillips SM. Resistance exercise-induced
increases in putative anabolic hormones do not enhance muscle protein synthesis
or intracellular signalling in young men. J Physiol. 2009 Sep 7.

We aimed to determine whether exercise-induced elevations in systemic concentration of testosterone, growth hormone (GH) and insulin-like growth factor (IGF-1) enhanced post-exercise myofibrillar protein synthesis (MPS) and phosphorylation of signalling proteins important in regulating mRNA translation. Eight young men (20+/-1.1 y, BMI = 26+/-3.5 kg.m-2) completed two exercise protocols designed to maintain basal hormone concentrations (LH = low hormone) or elicit increases in endogenous hormones (HH = high hormone). In the LH protocol, participants performed a bout of unilateral resistance exercise with the elbow flexors. The HH protocol consisted of the same elbow flexor exercise with the contra-lateral arm followed immediately by high-volume leg resistance exercise. Participants consumed 25 g of protein after arm exercise to maximize MPS. Muscle biopsies and blood samples were taken as appropriate. There were no changes in serum testosterone, GH or IGF-1 after the LH protocol, whereas there were marked elevations after HH (testosterone, P < 0.001; GH, P < 0.001; IGF-1, P < 0.05). Exercise stimulated a rise MPS in the biceps brachii (rest = 0.040+/-0.007, LH = 0.071+/-0.008, HH = 0.064+/-0.014 %.h-1; P < 0.05) with no effect of elevated hormones (P = 0.72). Phosphorylation of the 70-kDa S6 protein kinase (p70S6K) also increased post-exercise (P < 0.05) with no differences between conditions. We conclude that the transient increases in endogenous purportedly anabolic hormones do not enhance fed-state anabolic signalling or MPS following resistance exercise. Local mechanisms are likely to be of predominant importance for the post-exercise increase in MPS.
 
I love that you keep posting interesting studies here, keep it up!

I'll give this a read later.
 
I haven't read it yet, but I'm guessing it has to do with local (signals originating from the muscles being worked on as a result of the muscle being worked. Only acting on the specific muscle itself) vs systemic (increases in for example hormones that affect the entire body) signals responses to training and which one has the most to say.

For example, testosterone (which is systemic) has been shown to increase as a result of an exercise session.. so has MGF (which is local).. now which one has the most to say for training adaptations?

Like I said, I haven't read the article, but I'm pretty sure that's what it's about.
 
Karky said:
I haven't read it yet, but I'm guessing it has to do with local (signals originating from the muscles being worked on as a result of the muscle being worked. Only acting on the specific muscle itself) vs systemic (increases in for example hormones that affect the entire body) signals responses to training and which one has the most to say.

For example, testosterone (which is systemic) has been shown to increase as a result of an exercise session.. so has MGF (which is local).. now which one has the most to say for training adaptations?

Like I said, I haven't read the article, but I'm pretty sure that's what it's about.
Click to expand...

Yeah, that's what I thought too, but it says that the hormones were elevated in the HH group, which is the one that showed increased MPS. So that doesn't make any sense. What am I missing?
 
they used two groups. one trained to get higher hormones, one trained to get no change in hormones. There was no difference in protein synthesis between the groups.
If the hormones played a big role in protein synthesis, the HH group should have had a higher protein synthesis than the LH group.

this is just what I'm getting from skimming the abstract before bed..
 
should also be noted that (it seems) they measured MPS just after the work out. It could be that it takes longer time for the systemic hormones' effect to kick in.
I'm pretty sure both testosterone and GH have some delay from when they are elevated in the blood to when their effects on protein synthesis are seen.
 
Karky said:
should also be noted that (it seems) they measured MPS just after the work out. It could be that it takes longer time for the systemic hormones' effect to kick in.
I'm pretty sure both testosterone and GH have some delay from when they are elevated in the blood to when their effects on protein synthesis are seen.
Click to expand...

Good point.

I get it now. It's just poorly worded. When it says that exercise increased MPS, it doesn't specifiy if they're referring to the LH or HH, and the last discussed group was HH, so I assumed they meant that. But if they meant in both groups MPS was equal, then it makes sense.

I find it hard to believe that HGH and Test don't play a part in MPS though, but I guess it's hard to argue with evidence.
 
I'm pretty sure they do play a part, but that you won't see it when you measure protein synthesis right after they got elevated.

I'm gonna read the entire thing later today or tomorrow, depending on when I have time.
 
Ride_On said:
I find it hard to believe that HGH and Test don't play a part in MPS though, but I guess it's hard to argue with evidence.
Click to expand...

Well it clearly does play a part, you just need to look at steroid use and synthetic HGH use to see that they can increase MPS. I imagine the study is looking at whether the increase in hormones that can naturally be generated after exercise is enough to create an increase in MPS
 
Typhon said:
Well it clearly does play a part, you just need to look at steroid use and synthetic HGH use to see that they can increase MPS. I imagine the study is looking at whether the increase in hormones that can naturally be generated after exercise is enough to create an increase in MPS
Click to expand...

Yeah, that was part of my thinking. It doesn't really matter if it is naturally created or not IMO. Testosterone is testosterone once it is made. Why would it be any different?

Karky I don't think you can get the full article, or at least I couldn't.
 
I think that if they had taken this study in a little different direction, along with a bit of an added MPS test wait time, this study could have ended very differently.

I think it's pretty clear that local stressors are going to generally have the most impact on stimulating adaptation. From the standpoint of the affect of growth hormones, I'm far more interested in how HH levels affected muscles that weren't exercised. They should have had time-delayed samples for muscles that weren't directly stressed to assess the impact of HH vs LH in non-localized tissues.
 
Hi,

That is nice,It is really a nice article.I am very interested for this topic.Please keep sharing more detail information related to this article.Thank you for sharing the comment..
 
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