Protein Liquid or solid?

Is
liquid or solid whole food proteins better?”

That
really is a loaded question since it depends on your definition of ‘better’.

Let’s
define ‘better’ as one that spikes plasma amino acid levels the fastest. After
all, amino acid delivery into the plasma is one of the potential triggers for
turning on muscle protein synthesis.

And
a high activation of muscle protein synthesis is the mechanism for recovery,
growth and adaptations from exercise training.

So…which
is the best for that??

At
least study set out to investigate the effects of ingestion of several
different protein sources on plasma amino acid levels.

Skim
milk, soy milk, beefsteak, eggs, and a liquid ‘meal replacement’ were compared.
Each food source provided 20 grams of protein and all proteins were relatively
similar in leucine content. While all provided similar total amino acid
availability, distinct patterns in the rate of amino acid availability were
observed.

Liquid
forms of protein produced high plasma amino acid profiles faster than the solid
foods- almost twice as fast (~50 minutes vs ~100minutes). Skim milk provided
the most rapid rise in peak concentrations of total amino acids (TAA),
essential amino acids (EAA), and branched chain amino acids (BCAA).

Skim
milk also produced an increased plasma leucine level faster than any other
protein source (~ 25 minutes). Soy consistently showed a lower and slower
plasma amino acid response.

Knowing
that leucine may in fact be a trigger of mTOR (a protein signaling pathway
involved in muscle protein synthesis), we can systematically choose appropriate
protein selections to insure the most rapid delivery of leucine, BCAA, and EAA
to the working muscles.

Based
on the information presented here, the ‘best’ protein source would be a liquid
protein source that has high concentrations of leucine and relatively little
fat and fiber allowing rapid delivered of amino acids; much faster than if a
solid food (or soy) matched for leucine content was ingested.

What
does this mean and why should I care?

Knowing
how certain protein rich foods affect your blood amino acid levels will allow
you to time the delivery of key nutrients to your working muscle more
effectively. Heading to hit the weights? Quick delivery of essential amino
acids (the ones responsible for muscle protein synthesis) would be a great
idea.

A
solid food meal that will require 180 minutes to produce peak blood amino acid
levels would NOT get the job done. Heck, you would be back at home resting on
the couch by the time that was digested and absorbed.

What
about after a workout, can I have a steak then? Absolutely! But only if you
want to delay the delivery of key nutrients necessary for recovery and growth.
Once again, utilizing liquid nutrition comprised of at least 10-15 grams of
essential amino acids will be the only way to ensure initiating optimal
recovery.

Based
on this new information, it might be tempting to recommend one particular type
of protein as best. However,  a more important frontier in performance
nutrition (to me at least) would be the structuring of meal patterns and plans
that not only create high levels of essential amino acids in circulation but
also provide the combination of protein sources that ensure the greatest net
protein gain from each feeding.

The
Metabolic Nutrition Coaching Systems give fitness professionals personal many
clear advantages. One is a cutting-edge approach to protein nutrition; the
clear science on the right type, timing and quantity to accelerate recovery,
muscle gains and fat loss.

Dr
Paul Cribb is an award-winning Scientist, Mentor & Coach to leading Fitness
 Professionals. Paul is the creator of mp-body.com
and The
Metabolic Nutrition Coaching Systems - the first ever science-based,
research-proven, nationally accredited coaching program.

Reference:
Burke L. et al Effect of Intake of Different Dietary Protein Sources on Plasma
Amino Acid Profiles at Rest and After Exercise. Int J of Sport Nutri and Exe
Metab 22, 452 -462.