Capacity of your body to utilize protein in a given meal (Joshua_Naterman)

The best data I have seen suggests a ~10.7g/hour limit for protein transport across the intestinal lumen into the blood. That’s for absorption. Not all foods absorb at the same rate, so you will not get the same amount per hour.

http://www.ncbi.nlm.nih.gov/pubmed/16779921 is the review.

Of course, not all foods pass through the digestive tract at the same rate either… larger solid food boluses, boluses with long chain fatty acids, and boluses with more solid food protein all tend to pass through slower, giving a prolonged absorption window. In the end, though, your maximal absorption will occur via repeated and overlapping fast-digesting protein pulses.

However, actual utilization is a lot more complicated.

For example, Alan Aragon has reviewed quite a lot of literature that suggests that sustaining prolonged elevation of blood amino acid levels beyond 4-5 hours offers no benefit and may actually suppress the anabolic response beyond that point. He believes that the research also suggests that people get their best results from eating every 4-5 hours, but I think that is only true with solid meals. I think that the truly dedicated can get better results by using smaller pulses of whey protein every 2 hours, but that is a scheduling hazard for people with a real life and Alan’s suggestion is clearly the best overall strategy for regular people in my opinion.

If that is accurate, then we are looking for pulses and there is limited use for either trying to keep a sustained peak absortion rate for more than 3-4 hours. Instead we would see better results by generating repeated peaks that drop down to near-basal levels before the next bolus is introduced. Large single doses do not appear to generate much of any additional total muscle protein synthesis vs a smaller 30g dose in the young or elderly:http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3197704/figure/F2/

Considering how rapidly whey protein appears to absorb, you could use many small doses to achieve this effect.

Overall protein utilization for muscle protein synthesis appears to hinge upon achieving a ~3g dose of leucine that is absorbed fairly rapidly. This corresponds to ~28g of whey protein, 36-38g of beef protein and ~42g of chicken protein.

Our bodies are capable of selectively absorbing more ‘important’ EAA like leucine when there is more total AA than can be absorbed in full present in the intestines.

This leucine peak appears to be the nutritional trigger for muscle protein synthesis in particular, so it is worth keeping that as a central piece of your strategy. A large, fast-absorbing bolus of protein like 30g of whey is going to maximize your actual muscle gain, because pretty much nothing in the body is perfectly linear and that includes the response to blood leucine concentration.

Boirie Y, Dangin M, Gachon P, Vasson MP, Maubois JL, Beaufrère B. Slow and fast dietary proteins differently modulate postprandial protein accretion. Proc Natl Acad Sci U S A. 1997 Dec 23;94(26):14930-5.

There is also more recent research that continues to find this to be true.

The effect is much more pronounced in the elderly, as their muscle tissue appears to become resistant to lower doses of leucine but nearly identically sensitive to the 3g dose that comes with 30g of whey when compared to 25 year olds. This suggests that older individuals should make an effort to consume 30g of protein at one time, instead of many small servings. The net effect is much larger when they get 30g, even though they absorb just fine.

Consuming proteolytic enzymes such as Aminogen (pancreatic enzymes) appears to raise the peak blood amino acid levels as well as how long the peak remains. This may cause downregulation of endogenous pancreatic enzyme production over time, and I do not believe there is any clinical data to suggest what a suggested on-off cycle of this strategy should look like.

http://www.jissn.com/content/5/1/10

Additionally, you need to provide the energy to support the use of the protein you absorb for anabolic processes to occur and exercise so that gene transcription related to increased protein anabolism is upregulated, triggering the additional post-exercise increase in muscle protein synthesis after feeding. Young and old have nearly identical responses.

http://www.ncbi.nlm.nih.gov/pubmed/8368290 There is a lot of newer replication.

Together this appears to allow us to run the following game plan:

1) Eat 40-50g of protein every 4-5 hours with a meal. You could also do 30g every 3 hours. That’s what I do most of the time, but I would really just match the intake to your schedule. The longer the gap between meals, the more important it will be to use real meats that are not super lean in order to sustain the gastric emptying so that the protein actually sustains you through the entire gap.

2) Engage in resistance training to maximize response to each meal.

3) If you are adventurous perhaps do 1 day on, 1 day off supplementation with pancreatic enzymes or brand-name Aminogen at a dose of 2.5g per meal. You could do 5g, but the benefit is only ~10% for doubling your costs and is more likely to cause issues, so I don’t recommend that approach personally. It is probably wise to also take 1-2 weeks off every 2-3 weeks, as a precaution.

It’s simply impossible to say whether #3 would actually result in additional muscle mass gain… I don’t know if there is data out there on that, and I can’t guarantee safety, so I would consider this to be a risk that you would choose to take knowing that there are no guarantees, as opposed to an evidence-based recommendation. There were no indications of the potential for harm in the available research, but that doesn’t mean all the bases were covered and there is a very small body of research.

Publicités

How does internal rotation at the hips (of the femur) or the amount of internal rotation one has help in the squat? (failon)

First, the provocation test for femoral acetabular impingment is combined flexion, adduction, and internal rotation – essentially a knee-caved squat postion. This is a provocation test because it replicates an impingement and pinches the irritated tissue together. Producing this movement under load is a good way to injure yourself, but that’s not really what you’re asking about. Lire la suite

Effects of fatigue from resistance training on barbell back squat biomechanics.

The technique changes that occur in high repetition sets do not favor optimal strength development and may increase the risk of injury, clearly questioning the safety and efficacy of such resistance training programming. This is likely a display of self-preservation by individuals who are faced with high repetition programs.

http://www.ncbi.nlm.nih.gov/pubmed/24662156

Against the stream: relevance of gluconeogenesis from fatty acids for natives of the arctic regions

http://www.circumpolarhealthjournal.net/index.php/ijch/article/view/18436

Conclusion. In summary, our study sheds new light on our understanding of the metabolic state of natives from the arctic regions on their traditional diet. Moreover, they provide an avenue for new analyses that can reveal how humans have adapted metabolically to a practically carbohydrate-free diet.

Rippetoe Squatting (Glenn Pendlay)

1) There is the assumption that high bar squats, done very deep, do not work the posterior chain. I would propose that they do, and the difference between high bar and low bar and the posterior chain is not as large as some would assume it is.

When I converted from PL to OL, I converted from low bar, powerlifting type squats (medium stance) to closer stance high bar squats with a fairly upright torso, although I dont think my torso was ever as upright as some coaches would prefer. I remember my lower back and glutes being very sore over the first couple of workouts, these workouts were with weights around 365lbs to 405lbs. For comparison, my last heavy low bar back squat set done before this was 730lbs for a set of 3, to be fair this was with suit and wraps. I still remember that set, done in the left hand squat rack in the back of Rip’s old gym, because it was supposed to be a set of 5, and I lost my balance and dumped it on the pins on the 4th rep.

My observations at the time were that the longer lever arm created by putting the bar higher on the back was overriding the decreased angle of the back, and making it even harder for my lumbar muscles to maintan a tight back and for my hip extensors to extend the hip. I am not trying to say that HB squats work the posterior chain more than LB squats, I do not personally believe this, I am just making the point that the differences are not as clear cut as some are making them.

2) As I see it, the heart of this argument is really about the carry-over of LB and HB squats to other things, specifically OL. Here are a few general observations about carry-over.

When I was a good LB squatter, that strength did not carry over well to HB or front squats, as evidenced by some of the numbers above. When later in my lifting career, I became a decent HB squatter, it directly and immedietly carried over to being able to do very respectable numbers in the LB squat. My front squat of 550lbX5reps and HB back squat of 606lbsX10 reps, both done without a belt, these sets done about a month apart, allowed me to do several very, very respectable LB squats, and LB box squats with no practice or training on either the LB squat or the LB box squat. My feeling was that strength gained from HB squatting was just more « transferable » to other things than strength gained from LB squatting. Through many conversations with others, and a fair bit of experience coaching ex-powerlifters in the Olympic lifts, I have found that this seems to be quite universal. HB, Olympic style squatting will make you strong at the LB squat, LB squatting with a more bent over stance and less depth will NOT carry over well to the HB, Olympic style squat. I think the carry over from one to another bears considering, because what what we are really talking about here is the carry over from one type of squat or another to a completely different exercise.

Fred Hatfield, AKA « Dr. Squat » who is a respected authority on strength training, has written a couple of very good books on the subject, and who competed at a fairly high level in both gymnastics and OL before achieving a 1008lb squat at 44 years of age and I believe around 255lbs, has argued extensively that not only should the HB squat be used EXCLUSIVELY for the training of athletes, but its qualities of carry over are such that even POWERLIFTERS who are actually competing with a low bar, bent over, only to parallel and sometimes wide stance squat, should in fact do HB, Olympic style squats for much of the off season. In a rough quote of his words, HB squats build strength, LB squats demonstrate it.

3) Positions become habit, and I have not seen much about this in the specific arguments over Olympic lifters doing one type of squat or another. I remember when I was first starting the Olympic lifts, the hardest thing in the world for me was to catch a heavy clean with a torso upright enough to hold the bar on the shoulders, and not let it roll off. The second hardest was to stand up with it without sticking the but immedietly out, and raising the hips first, and dumping the bar off the shoulders, even though had I been magically able to glue the bar in place, I had plenty of strength to stand up with it. I believe that at least part of this was very simply that I was used to this position from doing so many squats this way, and whenever anything was heavy, I , without thinking, reverted back to it. It was a hard, hard habit to break, one I really never completely broke. I would propose that for Olympic lifters, it is better, as a rule, to have the torso and hips in the approximate position that they need to be in when you are going to be in that hole in competition every time you are in that hole in training.

4) A bit has been said about relative strength, and the weak hamstrings of Olers… or more specifically the relative strength of OLers hamstrings and thighs leaving them quite quad dominant. I would propose that OLers SHOULD be more quad dominant given the demands of the sport, and that given a solid diet of nothing but the competitive lifts only, with no assistance exercises, you would develop a quad dominant athlete. A quad dominant athlete will be much more likely, when the weights get heavy, catch a clean with an upright torso and stand without kicking the hips way out, and to dip and drive straight on the jerk. With maximal weights, the body has a way of getting into its strongest positions naturally, and for a quad dominant lifter, the strongest positions are the right ones for the sport, and the ones that will allow successful lifts with the greatest weight. I think that part of my problem successfully catching cleans early in my OL career was due to the « bad habit » of being leaned over too far in the bottom of a squat, but another factor was that I was, at the time, quite hamstring/posterior chain dominant. The wrong recipe for success in OL.

5) The last thing, one that I havnt seen touched on, is ease of coaching. A high bar position is pretty natural. Its where most people will put the bar without being coached. Its also pretty comfortable for the vast, vast majority of people. No undue strain on the back, neck, shoulders, or wrists. On the other hand, a low bar squat usually has to be coached, to get the wrist and hands and bar all in the right position, it often has to be coached extensively. It is not unusual for it to cause shoulder pain, or wrist pain if the shoulders/arms are too tight to keep the hands and wrist in the right position. In my experience it is, at the least, initially uncomfortable.

I remember all kinds of shoulder pain when I was squatting low bar as a powerlifter. Literal cramps in the shoulder muscles during sets of 5, shoulder pain the next day, etc. And I remember that it was bad enough that it interfered with my bench press training at times. This is an experience shared by many, many powerlifters. One thing that was great when I switched to HB squats was that the shoulders no longer hurt! It was great to be able to do a hard squat workout, and not have my shoulders and/or wrists hurting as bad as my legs!

Carrying heavy weights in that low bar position is just plain hard and fatiguing on the sholders. For many people, if you dont NEED to do it that way, I am not sure why you would.

To be fair, I think squats done the way Rip coaches them are great. A great exercise. The guy certainly knows how to teach people to squat, hes proven that many times, and someone squatting with form acceptable to him is squatting in a more productive and safe manner than the vast majority of those squatting. I also think the HB vs LB controversy has less meaning than has been assigned to it… for example, one certainly can squat with the bar in a low position and still do a pretty upright, deep squat, that as far as body position would satisfy any Olympic lifting coach. One can also do a HB squat and get quite bent over, I have personally proven that many times! Simply changing the position of the bar on the back doesnt magically change a good exercise to a bad one, or vice versa.

But, Olympic lifting is a sport, and it is pretty universally agreed by those with extensive experience as athletes and coaches in that sport that there is an advantage in that sport to be gained from squatting in a certain way, and that way is a high bar, upright squat. I do agree with this.

I am not so sure that I agree with Fred Hatfields view that HB, Olympic style squats are so superior and have such a superior strength transfer to other activities that not only all athletes should be doing it that way, but even competitive powerlifters who compete with a low bar squat should do much of their training with the HB squat. I am inclined to think in this direction, but it is certainly not as clear cut an issue as the one pertaining to OLers. Fred’s accomplishments and achievements do lend some credibility to his views though.

glenn

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