Part G: Study Discussions

What are your thoughts on the following BCAA study?

J Nutr. 2006 Jan;136(1 Suppl):234S-6S.
Modulations of muscle protein metabolism by branched-chain amino acids in normal and muscle-atrophying rats.

Kobayashi H, Kato H, Hirabayashi Y, Murakami H, Suzuki H.

Applied Research Department, AminoScience Laboratories, Ajinomoto Co., Kawasaki, Japan.

It has been shown that BCAAs, especially leucine, regulate skeletal muscle protein metabolism. However, it remains unclear how BCAAs regulate muscle protein metabolism and lead to anabolism in vivo. We examined muscle protein synthesis rate and breakdown rate simultaneously during BCAA infusion in muscle atrophy models as well as in normal healthy rats. Corticosterone-treated rats and hindlimb-immobilized rats were used as muscle atrophy models. Muscle protein synthesis rate and breakdown rate were measured as phenylalanine kinetics across the hindlimb. In anesthetized normal rats, BCAAs stimulated muscle protein synthesis despite low insulin concentration and did not suppress muscle protein breakdown. In corticosterone-treated rats, BCAAs failed to restore inhibited muscle protein synthesis, but reduced muscle protein breakdown. Immobilization of hindlimb increased muscle protein breakdown within a day. BCAAs did not change muscle protein metabolism, although essential amino acids (EAAs) suppressed muscle protein breakdown in hindlimb-immobilized rats. We also evaluated changes of fractional synthesis rate (FSR) of skeletal muscle protein during infusion of leucine alone or EAAs for 4 h in anesthetized normal rats. FSR showed a transient increase at 15-30 min of leucine infusion and then declined, whereas FSR stayed elevated throughout EAA infusion. We concluded that

1) BCAAs primarily stimulate muscle protein synthesis in normal rats independently of insulin
2) EAAs are required to maintain the BCAA stimulation of muscle protein synthesis and
3) The effects of BCAAs on muscle protein metabolism differ between atrophy models.

Then I would like to see them explain Josh & Tracy Anthony’s data showing that leucine alone will stimulate protein synthesis for about 2 hours.

Follow up to the answer above:
Thanks, I take your word above theirs. To play it safe i am thinking , primal eaa pre workout, with xtend + wms + whey (because i like it) post. I may also add wms pre workout, because i hear that it high gi carbs stimulate protein synthesis even more pre workout than post.

The other point to make is that unless you workout in the morning without eating, and you eat like a typical bodybuilder (eating frequently) there will NEVER be a point during the day where you don’t have ample levels of EAA available to maintain synthesis

On consuming amino acids+ carbs before exercise

Why don’t you advocate having higher gi carbs before as well as after a workout?

Tipton KD, Rasmussen BB, Miller SL, Wolf SE, Owens-Stovall SK, Petrini BE, and Wolfe RR. Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise. Am J Physiol Endocrinol Metab 281: E197-206, 2001.

here is what the study indicated – These results indicate that the response of net muscle protein synthesis to consumption of an EAC solution immediately before resistance exercise is greater than that when the solution is consumed after exercise, primarily because of an increase in muscle protein synthesis as a result of increased delivery of amino acids to the leg.

I have a problem with the method they use to measure synthesis as it requires a ‘steady state’ and exercise is NOT steady state

On Protein combinations:

What you mention about absorption got me thinking back to this study with some trainers throw around alot lately. It says basically Casein + Whey mix is superior to Whey + carb or Whey + Bcaa + Glutamine (close to what I do but i use 10 G BCAA) in terms of body mass improvement results. Thus some were recommending to lifters :
20 G of Casein + 20 G Whey pwo (even though the study itself seems to use 40 Whey + 8 Casein). Check the link below:

The Effects of Protein and Amino Acid Supplementation on Performance and Training Adaptations During Ten Weeks of Resistance Training

I dunno if your familiar with this study. What do you feel about it? Marketing over hype to get us to buy more expensive casein ($10+/lb) ? What is really ideal pwo wise? These things influence my purchases. I know WHEY is needed but casein is expensive. Hell I may even start using WHey + 1-2 Table Spoon of Flaxseed Oil at bedtime from what you said. I had no idea.

They didn’t really control any variables in the rest of the diet throughout the rest of the day… makes it tough to draw conclusions

On the interactions of caffeine and creatine:

2002 Nov;34(11):1785-92
Caffeine is ergogenic after supplementation of oral creatine monohydrate.

Doherty M, Smith PM, Davison RC, Hughes MG.
Department of Sport, Exercise and Biomedical Sciences, University of Luton, United Kingdom.
PURPOSE: The purpose of this investigation was to assess the acute effects of caffeine ingestion on short-term, high-intensity exercise (ST) after a period of oral creatine supplementation and caffeine abstinence. METHODS: Fourteen trained male subjects performed treadmill running to volitional exhaustion (T(lim)) at an exercise intensity equivalent to 125% VO(2max). Three trials were performed, one before 6 d of creatine loading (0.3 g x kg x d(-1) baseline), and two further trials after the loading period. One hour before the postloading trials, caffeine (5 mg x kg(-1)) or placebo was orally ingested in a cross-over, double-blind fashion. Four measurements of rating of perceived exertion were taken, one every 30 s, during the first 120 s of the exercise. Blood samples were assayed for lactate, glucose, potassium, and catecholamines, immediately before and after exercise. RESULTS: Body mass increased (P < 0.05) over the creatine supplementation period, and this increase was maintained for both caffeine and placebo trials. There was no increase in the maximal accumulated oxygen deficit between trials; however, total VO(2) was significantly increased in the caffeine trial in comparison with the placebo trial (13.35 +/- 3.89 L vs 11.67 +/- 3.61 L). In addition, caffeine T(lim) (222.1 +/- 48.9 s) was significantly greater (P < 0.05) than both baseline (200.8 +/- 33.4 s) and placebo (198.3 +/- 45.4 s) T(lim). RPE was also lower at 90 s in the caffeine treatment (13.8 +/- 1.8 RPE points) in comparison with baseline (14.6 +/- 1.9 RPE points). CONCLUSION: As indicated by a greater T(lim), acute caffeine ingestion was found to be ergogenic after 6-d of creatine supplementation and caffeine abstinence.

Caffeine may (not proven) have some negative effects on the creatine transporter but I believe that if you are taking 5g of creatine per day that is going to be enough to override those effects and still saturate the muscle cell.


On mixed-muscle fractional synthesis rate (FSR)

If you get a minute to give your input on this one, it would be appreciated.
2 studies here on mixed muscle FSR :

Aging does not impair the anabolic response to a protein-rich meal.
Symons TB, Schutzler SE, Cocke TL, Chinkes DL, Wolfe RR, Paddon-Jones D.

Division of Rehabilitation Sciences, The University of Texas Medical Branch, Galveston, TX 77555-1144, USA.

BACKGROUND: Sarcopenia is a debilitating condition afflicting the elderly that may be facilitated by insufficient or ineffectual intake of dietary protein. We previously showed that free-form essential amino acids acutely stimulate muscle protein synthesis in both the young and the elderly. However, the ability of an actual protein-rich food to stimulate anabolism in the young and the elderly has not been explored. OBJECTIVE: We aimed to characterize changes in plasma amino acid concentrations and to quantify muscle protein synthesis in healthy young (41 +/- 8 y old; n = 10) and elderly (70 +/- 5 y old; n = 10) persons after ingestion of a 113-g (4-oz) serving of lean beef. DESIGN: Venous blood samples and vastus lateralis muscle biopsy samples were obtained during a primed (2.0 mumol/kg) constant infusion (0.08 of l-[ring-(13)C(6)] phenylalanine. Plasma amino acid concentrations were measured and a mixed-muscle fractional synthesis rate (FSR) was calculated during the premeal period and for 5 h after beef ingestion. RESULTS: Mixed-muscle FSR increased by approximately 51% in both the elderly (mean +/- SE measurements: 0.072 +/- 0.004%/h and 0.108 +/- 0.006%/h before and after the meal, respectively) and the young (0.074 +/- 0.005%/h and 0.113 +/- 0.005%/h before and after the meal, respectively) after beef ingestion (P < 0.001). Plasma amino acid concentrations peaked at approximately 100 min after beef ingestion in both age groups but were substantially higher in the elderly (2185 +/- 134 nmol/mL compared with 1403 +/- 96 nmol/mL; P < 0.001). CONCLUSION: Despite differences in the concentration of amino acids in the plasma precursor pool, aging does not impair the ability to acutely synthesize muscle protein after ingestion of a common protein-rich food.


Differential stimulation of muscle protein synthesis in elderly humans following isocaloric ingestion of amino acids or whey protein.
Paddon-Jones D, Sheffield-Moore M, Katsanos CS, Zhang XJ, Wolfe RR.

Department of Surgery, The University of Texas Medical Branch, and Shriners Hospitals for Children, Galveston, Texas 77550, USA.

To counteract the debilitating progression of sarcopenia, a protein supplement should provide an energetically efficient anabolic stimulus. We quantified net muscle protein synthesis in healthy elderly individuals (65-79 yrs) following ingestion of an isocaloric intact whey protein supplement (WY; n=8) or an essential amino acid supplement (EAA; n=7). Femoral arterio-venous blood samples and vastus lateralis muscle biopsy samples were obtained during a primed, constant infusion of L-[ring-2H5]phenylalanine. Net phenylalanine uptake and mixed muscle fractional synthetic rate (FSR) were calculated during the post-absorptive period and for 3.5 h following ingestion of 15 g EAA or 15 g whey. After accounting for the residual increase in the intracellular phenylalanine pool, net post-prandial phenylalanine uptake was 53.4+/-9.7 mg phe leg-1 (EAA) and 21.7+/-4.6 mg phe leg-1 (WY), (P<0.05). Postabsorptive FSR values were 0.056+/-0.004% h-1 (EAA) and 0.049+/-0.006% h-1 (WY), (P>0.05). Both supplements stimulated FSR (P<0.05), but the increase was greatest in the EAA group with values of 0.088+/-0.011% h-1 (EAA) and 0.066+/-0.004% h-1 (WY), (P<0.05). While both EAA and WY supplements stimulated muscle protein synthesis, EAAs may provide a more energetically efficient nutritional supplement for elderly individuals.

Compared to beef :

Mixed-muscle FSR increased by approximately 51% in both the elderly (mean +/- SE measurements: 0.072 +/- 0.004%/h and 0.108 +/- 0.006%/h before and after the meal, respectively) and the young (0.074 +/- 0.005%/h and 0.113 +/- 0.005%/h before and after the meal, respectively) after beef ingestion (P < 0.001).

Question: Is mixed muscle FSR increased greater from a beef meal than whey or EAA’s? So this is 2 separate studies but is beef showing better muscle protein synthesis with these greater values in FSR rates?

EAA group
0.088+/-0.011% h-1
Whey group
0.066+/-0.004% h-1
Beef Meal (elderly)
0.072 +/- 0.004%/h before to 0.108 +/- 0.006%/h after
Beef Meal (young)
0.074 +/- 0.005%/h before to 0.113 +/- 0.005%/h after

You cannot compare FSR rates from separate studies. There was a study done on this recently that showed qualitative comparisons are ok (changes from fasted to fed) but comparing absolute rates has too much error.

In short, don’t compare them. Do you know if they all used the same tracer? Same infusion/dose protocol? How did the homogenize the tissue? what column did the use for the GCMS? There are too many variables to make comparisons.