Of some interest was that more protein did in fact have a larger impact on protein synthesis which goes against the previous studies on this. There are a couple of possible reasons for this. One is different in study methodology. Part of this has to do with differences in the sources of protein used. The studies which found a maximal effect of 20-25 grams used egg protein, this study used whey. Differences in or could play a role here; we know that leucine is a key player in this and dairy proteins (and surprisingly ) have the highest concentrations. Not a lot of comparative work has been done looking at different proteins (although ) and most use protein powders or isolates. Perhaps whole food would be different.
A final comment, from a result I didn’t mention above. The researchers did find that, while more protein increased protein synthesis to a greater degree, the absolute measured response was still about 75% of the response seen in the earlier studies on leg training only. That is, training the full body led to a decreased response in MPS overall compared to leg training only. The researchers speculate that this is due to the ingested amino acids being more dispersed over the body to support the changes in all muscle groups.
Whey Protein shakes have become one of the most popular protein supplements in the market. But what truly is whey protein and where does it come from? Whey is the liquid material which is created as a by-product of cheese making. Whey protein is a mixture of the globular proteins which are isolated from this liquid. Cow milk contains 20% whey protein while mother’s milk contains as much as 60% whey. It is one of the fastest and easiest digesting proteins.
Certainly some of this is just due to the fact that you can only put enough intense training into so many things at once. A runner only runs, a triathlete has to spread their training across three events (and many are starting to focus on a single event while maintaining the others to bring them up). But I’ve theorized that the body has limited adaptational capacities, you can only adapt so many things at once. And this study, very obliquely supports that. The protein synthesis response (which was only measured in the quads) was lower when the full body was trained compared to earlier studies that only used leg training.
This is the cheapest and most common form of whey. The mixture has been processed to primarily contain protein, hence its name. The protein content of the mixture may vary from 29% for low grade mixes to 89% in high grade mixes.
Would even more protein overcome this? That is, if you’re trying to support growth in more total muscle mass (and here I’m talking about more muscle groups, not a guy with slightly bigger biceps than another), would eating even more protein raise MPS in all those muscle groups to reach the same level. The body only has so much blood and one aspect of increased protein synthesis and nutrient delivery following training is increased blood flow. Perhaps the body simply can’t deliver nutrients to all worked muscles no matter wat you do.
But MPS was different, though in the opposite direction to phosphorylation of this marker which further supports it as not indicating much. While the difference wasn’t huge more protein did in fact stimulate more MPS. I’ve presented the results below. That is, more protein stimulated more protein synthesis following training. I’ve shown the results below.
This form of whey has a protein content of mostly 90% by definition. It starts out as a concentrate and is then further processed to remove even more lactose and fat. The advantage WPI’s have over WPC’s is the lower content of fat, lactose and sugar.
The study made a few interesting observations. The first is that leucine appearance was slightly faster with the 20 grams whey dose versus the 40 gram whey dose with the peak occurring at 30 minutes versus 60 minutes. Not surprisingly, leucine levels were higher at all time points with the larger amount of protein. Also not surprisingly intracellular levels of leucine were higher with the larger amount of protein. Amino acid oxidation (burning of aminos for energy) was also higher with the higher dose but this too is not that surprising as amino acids in excess of what can be used tend to be burned for energy. Honestly, none of this is surprising since you would expect more protein to release more amino acids into the bloodstream and that this would transiently affect the amount in the muscle itself.
Whey Protein Hydrolysate are also called “pre-digested proteins”. These proteins are the easiest to absorb. WPH’s also help the body to produce more insulin and have a lower fat, sugar and carb content.
On both test days the subjects were fed a standardized breakfast, waited 2 hours and were then infused with a radioactive tracer and all of the other boring technical stuff that was done. They waited one hour and performed a full body weight training workout consisting of chest press, pulldown, leg curl, leg press and leg extension. Leg work was done one leg at a time and they did 3 sets of 10 at 75% 1 repetition max followed by a fourth set to failure. Reps were done on a 1 second up, 2 seconds down cadence. The second workout was matched to the first and each group consumed either 20 or 40 grams of whey protein after a biopsy was taken and both groups did both amounts of protein with a 2 week washout. A second and third biopsy were taken 3 and 5 hours later at which point the study ended.
The protein you consume should be compatible with your body. Always consult a professional, especially if you have any known medical conditions, before supplementing your diet.
Ignoring that, there is still interest in the topic, primarily in terms of what might be the optimal dose of protein to support muscle growth. For several years now, an idea has been floating . Please note that I said synthesis. There is also the issue of muscle protein breakdown (MPB) and it’s the combination of the two that determines that happens to muscle. . Unfortunately, it was looking at whole body protein breakdown and not skeletal muscle specifically.