Protein Timing Reloaded: A Reminder on the Importance of Repeated 20g Pulses for Optimal Protein Synthesis
Protein timing & dosage matter for protein synthesis in the PWO window. |
Note: This paper is actually an almost identical clone to a previous paper by the same groups of researchers (Moore. 2012). Since I've discussed that back in 2012 already, I still decided to include it in this week's SuppVersity line-up, because it fits in perfectly with the previously discussed study on the benefits of protein intakes >2x RDA and that simply eating more protein is not really gonna cut it. If you want to read up on the corresponding SuppVersity article discussing the 2012 study, you can do this right here.
More is only more if it's adequately timed & distributedThe scientists knew from countless previous experiments that a single bolus of∼20 g of protein after a bout of resistance exercise would provide a maximal anabolic stimulus during the early post-exercise recovery period (∼5 h). The "effect of various protein feeding strategies on skeletal muscle protein synthesis during an extended recovery period (12 h)" (Areta. 2013) was yet largely unknown. In order to shed some light onto the protein-anabolic response in this "post-post-workout window", the researchers compared three different patterns of ingestion of 80 g of protein during 12 h recovery after resistance exercise and the associated anabolic response in human skeletal muscle:
- 10, 20 or 40 g feedings using a pulsed, intermediate or bolus ingestion regimen, respectively
- consumed after 4x10 reps @ 80% of the 1 RM with 3 min rest between sets
So what's the deal, then?
The "anabolic window" turns out to be more of a barn door, which is unlocked by the key of exercise and nutrition science (learn more) |
"[...] rates of myofibrillar protein synthesis (MPS) remain elevated above rest throughout 12 h of recovery when a single bout of resistance exercise is followed by the partitioned ingestion of 80 g of high quality protein. Furthermore, we show that daily rates of protein synthesis were highest with regular (i.e. every 3 h) intake of a moderate (20 g) quantity of rapidly digested whey protein." (Areta. 2013)Areta et al. specifically emphasis that the acute stimulation of the nutrient and contraction-sensitive intracellular signalling network is thus not the main determinant of net protein synthesis in the huge post-anabolic window.
A word of caution: Before you freak out totally about how big you're going to be next week, now that you follow the optimal protein supplementation regimen, I suggest you take a look at Alan Aragon and Brad Schoenfelds paper on the purported and real benefits of protein timing and its real-world implications | read more ...
The anabolic effects of the intermediate supplementation do yet only appear to be. Over the whole study period, they are not statistically different and the superiority in terms of the actual fractional protein synthesis (FSR) persists, even when
using a mean intracellular enrichment from the other
groups. Thus an increase in intracellular enrichment cannot be the underlying mechanism for the increase in fractional synthesis rates in the intermittent supplementation trial (INT) the researchers ascribe to an optimized
interplay between resistance exercise, time between
ingestion, and the total quantity (20g = at the critical threshold) of each (whey) protein feeding. The optimally timed and adequately dosed ingestion of 4 servings of 20g of whey could thus haveNow, this may appear counter-intuitive at first, after all the aminoacedemia in the intermediate trial does not appear to be more pronounced than that in the pulse trial and certainly inferior to the one of the bolus trial. This is in fact true, but it is a mere consequence of much greater %-ual absorption of the amino acids in the intermittent trial compared to both the bolus and pulse supplementation, of which the former are 'protein wasting' and the latter simply insufficient to fully trigger the protein synthetic response.
One thing to keep in mind, when you look at the results of the study at hand is the fact that this is just another acute resistance training study that employs an unrealistic (leg extensions only) workout. In other words, we cannot simply take for granted that statistical significant difference in short term protein synthesis (12h is still short) will also translate into measurable, let alone visible improvements in muscle hypertrophy. Still following the protocol outlined to the left is certainly not going to hurt you.
Bottom line: It should not really be necessary that I actually formulate another bottom line. If you stick to my basic recommendations (outlined among others in my interview with my buddy Sean Casey) you will do something very similar with your 3-5 meals with 30+g of quality protein each. The only thing that may be worth adding to it is a re-emphasis on the interaction of timing and dosing. You need at least 20g of leucine-rich protein to kickstart protein synthesis and - as of now - it looks like those will not sustain maximal protein synthesis for longer than ~3h before you have to 'refuel' the amino acid pool and (probably more imporatantly) 'reignite" the protein synthetic machinery with another 20g+ bolus of whey.
In view of the fat that proteins with a low(er) leucine content will probably need to be ingested in higher amounts I would still stick to the '30g+ rule' - after all, I assume you won't want to live off whey protein supplements and Quest Bars, only - do you?
Important additional read: "Evidence From the Metabolic Ward: 1.6-2.4g/kg Protein Turn Short Term Weight Loss Intervention into a Fat Loss Diet" | read more...
References:
- Areta JL, Burke LM, Ross ML, Camera DM, West DW, Broad EM, Jeacocke NA, Moore DR, Stellingwerff T, Phillips SM, Hawley JA, Coffey VG. Timing and distribution of protein ingestion during prolonged recovery from resistance exercise alters myofibrillar protein synthesis. J Physiol. 2013 May 1;591(Pt 9):2319-31. doi: 10.1113/jphysiol.2012.244897. Epub 2013 Mar 4.
- Moore DR, Areta J, Coffey VG, Stellingwerff T, Phillips SM, Burke LM, Cléroux M, Godin JP, Hawley JA. Daytime pattern of post-exercise protein intake affects whole-body protein turnover in resistance-trained males. Nutr Metab (Lond). 2012 Oct 16;9(1):91.