"20g or 40g of Whey?" That's the Wrong Question, When 4-5x 20-25g from Different Sources Would be the Answer!

Image 1: There could be a reason that your favorite protein powder comes with a scoop and a suggested serving size of 25-30g protein (max.)
If you could just pick one dietary supplement to take to desert island, what would it be? Creatine? Unquestionably a good choice. Yet even if the local fauna provided you with unlimited amounts of eggs, meats and fish, a whey protein powder, or I should say a leucine-rich complete protein source would probably be a better choice. Despite the fact that I am still skeptical as far as the real world significance of supplementally augmented post-exercise increases in fractional protein synthesis as the main, let alone exclusive determinant of skeletal muscle hypertrophy is concerned, it is undebatable that the delicate balance between protein breakdown and synthesis is at least the most obvious and, in the short term, probably in fact the most influential contributor to muscle growth.

"Only 1.2 - 1.6 protein per kg/day!?" - Calm down! The total amount is not all that counts

According to the latest installment of the "A to Z of Nutritional Supplements" series in the British Journal of Sports Medicine (the part on protein was - you may already have guessed it - co-authored by no one else but Stuart Phillips) the "current scientific evidence" suggests that
  1. daily intakes higher than the RDA, to be precise, 1.2-1.6g/kg body weight,
  2. an emphasis on leucine-rich protein sources (I suggest dairy, alternatively pea protein),
  3. multiple servings of 20-25g of protein / protein-rich foods spread equally across the day,
  4. an additional protein shake immediately after your workout
"should be very effective at allowing repair, remodelling and adaptation, and gains in lean mass in athletes" (Phillips. 2012).

Quality, Consistency and frequency over gluttony

For an 80kg athlete this would translate into a total protein intake of 96-128g of protein per day. Sounds pretty sparse, right? Well, if we just count proteins from meats, eggs, fish, dairy and dietary supplements and discard the protein from other sources, this would leave our 80kg athlete with max. 4-5 meals at which he would easily achieve the "threshold" limit of 25g; five opportunities to monetize on the dietary induced increase in protein synthesis; and five potentially protein anabolic spikes in plasma amino acid concentrations.
Remember: In the slowly abating hoopla around leucine people tend to overlook that despite its ability to set the protein synthetic machinery into gear, leucine needs the other EAAs and conditionally essential amino acids to get its muscle building job done.
And though the actual data does not provide any revolutionary new insights into the "ideal" amount of protein, a recently published study from Kevin D. Tiptons group at the University of Birmingham provides further evidence that everyone who strives to maximize skeletal muscle protein synthesis should be primarily concerned about the consistent and frequent (3) ingestion of quality (2) protein (Jackman. 2012).
Figure 1: Urea production (µmol/h/kg * 4h) and fractional myofibrillar protein synthesis (per hour) in the 4-hour recovery period after an intense leg workout and supplementation with either 20g or 40g of whey protein (data based on Jackman. 2012)
Despite the fact that there was a greater increase in fractional myofibrillar protein synthesis after the ingestion of 40g vs. 20g of whey protein after the 8 sets of 10 repetitions of leg presses and leg extensions the 30 previously resistance trained male subjects in the Jackman study had to perform, the +10% difference (+51% increase in MPS in the WP40, +41% in the WP20 group; increase expressed vs. placebo), the latter did not reach statistical significance over the 4h post workout period.

Diminishing returns with large vs. multiple bolus ingestions

Contrary to previous studies investigating the differential response to different amounts of dietary protein in the vicinity of a strength workout (cf. "Protein Synthesis Beyond the 20g Limit"), in which the subjects often trained in a fasted state, the Jackman study also confirms that the profound beneficial effects of immediate protein supplementation are retained, even if the last "protein rich meal" was consumed "only" 3h before the workout.
Figure 2: Experimental protocol of the Jackman study (based on Jackman. 2012)
This beneficial effect of repeated protein ingestion / protein timing stands in line with with the observation that Jackman et al. observed peak amino acid concentrations in the WP20 and WP40 arm of their study 15-30min and 45-60min after the ingestion of the respective amount of whey protein. From the fact that the latter went hand in hand with a statistically significant increase in insulin concentrations and +25% greater urea production in the WP40 trial, we can assume that a non-significant amount of the additional 20g of protein of the 40g whey protein shake was "abused" for gluconeogenesis instead of getting stored within the muscle tissue.

Image 2: The results Adelfo saw from the consistent intake of a perfectly timed mixture of fast and slow digesting proteins speak for themselves - intermittent fasting or not, consistency and frequency are key!
So, even if you don't care about "wasting" dietary protein, you better make sure to distribute your protein intake evenly within your "feeding window", with 20-25g of fast-digesting protein like whey every 2-3h, or a combination of fast digesting and slow digesting proteins (like whey + casein, or whey alone followed by a complete meal) every 3-4h to maintain a decently high and thusly "pro anabolic" level of amino acids in your blood stream while avoiding the hyperinsulinemic effects of larger boluses of whey protein. And if you don't think that this will work, or would be incompatible with the Intermittent Fasting protocol you have taken up as of late, I suggest you go through Adelfo Cerame's contest prep diet again, because with the lions share of his protein intake coming from very slow digesting "real food" protein sources (specifically meats and casein from cottage cheese and raw milk, cf. "3.2kg of Lean Mass With 40g of Casein Pre-Bed"), he strategically spiked with whey protein in the vicinity of his workouts - Adelfo achieved just that: a decent level of hyperaminoacidemia (=elevated serum amino acids) to make optimal use of the "24h Barn Door of Opportunity".