BCAA not good enough anymore?

[eliasmavs99]

I see a lot of people on their blogs taking 5-10g of Leucine. I know its an important BCAA but is it worth taking it separately or is what you get from BCAA's good enough? Insight?

[NO HYPE]

Originally Posted by eliasmavs99

I see a lot of people on their blogs taking 5-10g of Leucine. I know its an important BCAA but is it worth taking it separately or is what you get from BCAA's good enough? Insight?

This thread might have something to do with all the post-workout leucine/carb activity going on as of late....

Do post-exercise carbs actually help?

[eliasmavs99]

Thanks NOHYPE, I do remember reading through this thread last month. Thats probably where I got the idea. But still, Is it worth adding Leucine separately?

[NoNameNecessary]

Originally Posted by eliasmavs99

Thanks NOHYPE, I do remember reading through this thread last month. Thats probably where I got the idea. But still, Is it worth adding Leucine separately?

Yes. I do 10g of leucine post-workout as well as 5-10g of BCAA. There are tons of studies supporting the efficacy of leucine - search leucine on bb.com and pubmed.

[NO HYPE]

Originally Posted by eliasmavs99

BCAA not good enough anymore?

Originally Posted by eliasmavs99

Is it worth adding Leucine separately?

In my opinion, BCAA's will not elicit the same effect on protein synthesis as leucine/carbs post-workout.... hence the reason the study criteria isolated leucine as the key amino acid. In fact, there's a good possibility that using BCAA/carbs could significantly impede overall enhancement of protein synthesis, when compared to leucine/carbs alone.

Here's a good abstract on the relevance of leucine and protein metabolism....



Am J Physiol Endocrinol Metab 263: E928-E934, 1992;

Leucine as a regulator of whole body and skeletal muscle protein metabolism in humans

Leucine has been proposed as an in vivo regulator of protein metabolism, although the evidence for this in humans remains inconclusive. To test this hypothesis, we infused either L-leucine (154 +/- 1 mumol.kg-1 x h-1) or saline intravenously in six healthy men in two separate studies. L-Leucine infusion increased plasma concentrations of leucine and alpha-ketoisocaproate from 112 +/- 6 and 38 +/- 3 mumol/l to 480 +/- 27 (P < 0.001) and 94 +/- 13 mumol/l (P < 0.001), respectively, without any significant change in circulating insulin or C peptide levels. Leucine infusion decreased plasma concentrations of several amino acids and decreased whole body valine flux and valine oxidation (using L-[1-13C]valine as a tracer) and phenylalanine flux (using [2H5]-phenylalanine as a tracer). According to arteriovenous differences across the leg, the net balance of phenylalanine, valine, and lysine shifted toward greater retention during leucine infusion, whereas alanine balance did not change. Valine release and phenylalanine release from the leg (estimated from the dilution of respective tracers) decreased, indicating inhibition of protein degradation by leucine infusion. We conclude that leucine decreases protein degradation in humans and that this decreased protein degradation during leucine infusion contributes to the decrease in plasma essential amino acids. This study suggests a potential role for leucine as a regulator of protein metabolism in humans.