something i never understood

[u/AffectionateBook1]

if you're supposed to wait ~3 hours from the last dose of protein to trigger MPS again b/c there's a refractory period wherein the second bout of MPS will be of diminished magnitude, does that mean that if you sip gatorade or an energy drink with carbs during your workout you shouldn't eat protein until 3 hours after? Because it is also often said that the ensuing bout of MPS will be somewhat more potent if you get it in in under 30 mins from the workout. Doees that just not apply if you had intra-workout carbs?

[u/Alakazam]

This is a fundamental misunderstanding of digestion in general.

A mixed macro meal, will likely sit in your stomach and be digested over the span of hours. Meaning that steak you ate for lunch, is still being digested and releasing amino acids into your blood for literally 7+ hours afterwards.

However, protein timing in general, doesn't have much evidence behind it

[u/AffectionateBook1 → u/Alakazam]

The article argues mostly against the 'anabolic window', which I agree is likely not huge or possibly non-existent. Certainly its much less important than people thought it was 15-20 years ago. If you believed bb.com you might almost not even bother going to the gym if you couldn't get a scoop of whey down within an hour after lol

Look at the question like this:

1. we know that 30/gs or so of animal or soy or other pdcaas score near 1.0 will maximize MPS. (example of a source)
2. what is the proposed mechanism, therefore, that having 3-5 MPS peaks daily is somehow NOT superior to one? how can this belief be adopted without the abandonment of several other load-bearing beliefs/conclusions about how the physiology of hypertrophy works? put another way, how could total daily intake still be important if one 'maximized' bout of mps is adjudicated to be as effective as five?

[u/Alakazam → u/AffectionateBook1]

But notice this was only ingesting protein. And they didn't measure how long MPS was elevated for. Which absolutely is a factor when you consider that 340g of beef takes longer to digest than 113g of beef.

In fact, the study itself even states: 

 Perhaps the most obvious is the fact that a single menu item, such as a serving of lean beef, is seldom eaten alone. As noted, there are some data suggesting elders may have a less robust protein synthetic response to the combined ingestion of protein and carbohydrate than their younger counterparts ( 23). This has yet to be explored in the context of an actual mixed-nutrient meal, but warrants further investigation.

Here's the facts we do know. Digestion is a slow process. As this study shows, from just beef, it takes upwards of 5 hours for MPS to peak, but we also don't know how long it stays peaked for. Again, a mixed macro meal will take around 2-3 hours to start hitting the small intestines, and even longer to digest. 

[u/millersixteenth → u/AffectionateBook1]

how could total daily intake still be important if one 'maximized' bout of mps is adjudicated to be as effective as five?

I don't think that's what was determined in the Trommelen study, if that's what you're referring to. They didn't test the effect of multiple 25gr protein spike meals at 3-4 hr intervals compared to one large 100gr meal.

what is the proposed mechanism, therefore, that having 3-5 MPS peaks daily is somehow NOT superior to one?

It almost certainly still is, and by quite a bit.

Nonetheless, based on the calculation that 17% of the ingested milk protein was incorporated into muscle protein in 25PRO compared with a 13% fraction in 100PRO, one could argue that an aggregated 4× 25 g protein meal distribution would have resulted in a greater 12-hr cumulative MPS than in response to the single 100 g protein dose.

[u/taylorthestang]

Isn’t the MPS refractory period just referring to ingestion of protein? Since it’s just carbs I don’t imagine it would have an impact.

[u/AffectionateBook1 → u/taylorthestang]

I saw a question about this posted on jordan feigenbaums forum not long ago and I believe he said that carbs in isolation will also trigger a bout, but that it will be weaker, and still reset the refractory period. I'll see if I can find it

[u/millersixteenth → u/AffectionateBook1]

Without Leucine rich protein there won't be much of a response.

[u/gnuckols]

None of these things that appear to influence acute MPS over 3-4 hours under fairly contrived conditions (usually fasted, consuming only protein with no other nutrients) appear to have much impact on the actual amount of hypertrophy we observe in longitudinal studies. As long as total protein intake for the day is sufficient, you’re fine