# Article on maximising muscle protein synthesis by Layne Norton



## IronFed (Dec 10, 2008)

I've read through this article (pdf attached) and found it quite interesting so thought I'd share it with you all, not sure if it has been posted before it was written by Layne Norton, an American natural pro bodybuilder and skeletal muscle protein metabolism researcher.

I havn't got the best understanding when it comes to scientific terminology and I'm sure many here will understand it a lot better than I did, anyway I wrote a quick summary of the article below to the best of my understanding.

*Summary*

- Leucine is the key amino acid for stimulation of muscle protein synthesis.

- 3g of leucine is sufficient to maximise the anabolic response from a meal (A typical bb meal rich in protein will meet this e.g. 6oz chicken breast contains 3g leucine)

- Increases in plasma leucine trigger mTOR signalling and muscle protein synthesis, however sustained elevations of plasma leucine and mTOR signalling is not sufficient to maintain elevated protein synthesis which indicates a refractory response. So although an initial meal containing 3g leucine may trigger muscle protein synthesis it is unlikely that an additional stimulation can be achieved 3 hours later with a second meal of similar composition to the first, due to the refractory nature of muscle protein synthesis.

Solution to maximizing muscle protein synthesis over the course of the day:

- In order to avoid refractoriness and maximize muscle protein synthesis it may be best to consume a meal with larger doses of protein that contain sufficient leucine while allowing 4-6 hours before the next meal in order to allow amino acid levels to fall in between meals in order to re-sensitize the system.

- Another way to overcome refractoriness is to create a supraphysiological rise in plasma amino acid levels between meals (e.g. BCAA supplementation). A free-form amino acid supplement would likely be rapidly digested (even more so than whey) and elevate plasma amino acid levels above the previous meals plateau, especially when ingested with a carbohydrate source.

Reccommendations:

- Space protein rich meals at least 4 hours apart

- Consume a free-form amino acid supplement containing approx. 3g leucine (e.g. Serving of BCAA's or xtend) in-between meals

So what are your thoughts on this article?

From what I understand it seems to differ from a typical bb's meal schedule which is usually 6-8 meals a day spaced roughly 2-3 hours apart of roughly the same composition. Just wondering how much of a difference it would make?

Also, how does everyone else supplement with BCAA's? similar to this? intra-workout? pre and post workout? sip throughout the day? I'm ordering a large tub of xtend and giving the method in this article a go

cheers

manuscript[1].pdf


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## IronFed (Dec 10, 2008)

Bump


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## Big Bird (Sep 9, 2009)

4 hours!? i'd be starving by then =( not cool buddy


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## IronFed (Dec 10, 2008)

Big Bird said:


> 4 hours!? i'd be starving by then =( not cool buddy


I know it does seem like a long time inbetween meals but im assuming you would still eat the same amount of calories just spread over 4-5 meals instead of 6-8 along with 5g bcaa's inbetween meals


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## dtlv (Jul 24, 2009)

When he's talking about the refractory response of the body he's right - countless studies have shown that elevating levels of plasma amino acids stimulate protein synthesis as soon as they rise but the PS shuts off long before the levels have dropped down again.

Whilst they remain elevated after about thirty minutes there's no extra protein synthesis above the normal protein turnover occuring, so overdosing on the protein at this time may help you stay anticatabolic but won't necessarily help you grow more.

He seems to have forgotten though that it's not just Leucine that you need - leucine stimulates PS better than anything, but remember it takes all essential amino acids to build the muscle after the stimulation has occured, and the rate of PS is always limited by both the circulating essential amino acid you have the least of as well as the refractory response mentioned above... this makes EAAs a better option than just leucine IMO, although if diet is high enough on high quality proteins then just leucine is probably fine.

As for eating every four hours it's fine if you can get all the kcals you need this way, however some people can't eat big meals and need very frequent smaller ones... if you can eat less frequently though, leucine or EAA spiking between meals is a very good way to go, certainly it's what the studies suggest is optimum.


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## IronFed (Dec 10, 2008)

Thankyou for the response Dtlv74, much appreciated :thumbup1:

Do you supplement with BCAA's or EAA's in this way?


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## dtlv (Jul 24, 2009)

S_Tezza said:


> Thankyou for the response Dtlv74, much appreciated :thumbup1:
> 
> Do you supplement with BCAA's or EAA's in this way?


Yeah, much prefer EAAs (with a few extra BCAAs or leucine added) to whey... only need less than half the amount compared to whey but for the same benefit.


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## LJ98 (Dec 4, 2009)

dtlv said:


> When he's talking about the refractory response of the body he's right - countless studies have shown that elevating levels of plasma amino acids stimulate protein synthesis as soon as they rise but the PS shuts off long before the levels have dropped down again.
> 
> Whilst they remain elevated after about thirty minutes there's no extra protein synthesis above the normal protein turnover occuring, so overdosing on the protein at this time may help you stay anticatabolic but won't necessarily help you grow more.
> 
> ...


Sorry for digging up such an old thread.

If, due to the refractory response, PS can't be re-stimulated for 4 hours since last protein ingestion, does this mean a meal 2-3 hours after the last will be pretty much wasted and no additional PS will occur? If this is the case then what's the point of spiking with EAA's between meals?

I tend to have 3 large meals a day with 70-80g protein and 20g EAA intra-workout but not sure if this is optimal after reading Layne's article. Would it perhaps to be better to have 4 meals of 60ish grams protein so that I'm getting 4 (5 including the intra-workout EAA's) stimulations of PS a day instead of just 3?


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## dtlv (Jul 24, 2009)

LJ98 said:


> Sorry for digging up such an old thread.
> 
> If, due to the refractory response, PS can't be re-stimulated for 4 hours since last protein ingestion, does this mean a meal 2-3 hours after the last will be pretty much wasted and no additional PS will occur? If this is the case then what's the point of spiking with EAA's between meals?
> 
> I tend to have 3 large meals a day with 70-80g protein and 20g EAA intra-workout but not sure if this is optimal after reading Layne's article. Would it perhaps to be better to have 4 meals of 60ish grams protein so that I'm getting 4 (5 including the intra-workout EAA's) stimulations of PS a day instead of just 3?


Well there are a lot of variables involved. That post of mine quoted above, I still stand by all of it, but what I should have added is that the size and release/digestion speed of the protein in each main meal will radically affect the degree of benefit of an 'anabolic spiking' supplementation plan with between meal feeds of EAAs - if protein feeds are realtively small and easily digestable then spiking with EAAs between feeds should work like a charm, but with larger and more realistic bodybuilding type meals the effect should be less. Is arguable even that pretty much any whole food source of protein is going to ahve too slow of an amino acid release profile to allow for plasma aa levels to drop low enough anyway, even if meals are more than 4-5 hr apart.

My personal theory is that this spiking concept is only likely to work to any significant degree on an elemental diet where only individual amino acids and small amino acid peptides are consumed as dietary protein - with whole protein fractions plasma aa levels become very stable, and while this blunts anabolism slightly it also reduces catabolism, and the overall balance is pretty much the same -same end quantity for nitrogen retention, just slightly different process to get there - gotta love homeostasis!

IMO, in total honesty, I think its about the daily totals for quality protein that matter most, far more than the ingestion pattern.


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