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Razz
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I would THINK, but have not heard of such an evaluation done in a study, that determining which system is deficient (strength, meaning CNS efficiency and myofibril count; or endurance, meaning ability to process glycolysis metabolites) should determine what aspect of performance should be trained to improve VO2 marks the most. If you're already very metabolically capable you won't get much of any improvement from more endurance work as the percentile change of mitochondria and vascular density would be much smaller than someone who is deficient in this area. The same should go for strength training.

Given that hypothesis, I would add a second hypothesis that as strength generally takes longer to build than endurance the athletes who are strength deficient would see somewhat lesser gains in their VO2 marks than those who are endurance deficient.

From the results of this study, these things were not shown to be the case.

Firstly, everyone was untrained so they all had low endurance capability to begin with.

Secondly, there was no association between initial strength and change in VO2peak.

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Joshua Naterman

To be fair, there are a few things to take issue with. One, untrained athletes are hard to deal with because you simply don't know what their initial capabilities are. Some are naturally very strong and some have higher natural endurance. Without an initial performance evaluation it is hard to say whether there is any correlation. Second, all "endurance" methods are not comparable nor do they necessarily cause an appreciable increase in mitochondrial count. Regardless of WHY someone has a "poor" response to endurance training, the fact remains that for whatever the reason they are clearly not deficient in that part of the equation relative to the other variables. It therefore stands to reason, as I said previously, that if an individual is relatively more well-trained for endurance activities that strength training will have the most powerful effect on VO2 measures.

I JUST NOW took a look at the abstract. Here is a quote that 100% supports what I just said in my previous post. There is nothing to detract from it. I am glad I made that post before I looked, because it goes to show that I actually do have a fairly good understanding about what is going on in the body. Take a look.

... the group with the lowest response to endurance training increased VO2peak after the resistance training intervention
The worst endurance responders were the best strength responders. Hmm. That's exactly what I said.
The healthy males and females whose training response is low after endurance training seem to result in a marked improvement in their cardiorespiratory fitness by resistance training.
That's the last sentence. This time they say, in plain English, exactly what I proposed.

I do know what I am talking about! :lol:

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To be fair, there are a few things to take issue with. One, untrained athletes are hard to deal with because you simply don't know what their initial capabilities are. Some are naturally very strong and some have higher natural endurance. Without an initial performance evaluation it is hard to say whether there is any correlation.

Where did you draw the conclusion that there were no evaluations of their fitness capabilities before the study? Any good study does that!

In the study, people with the lowest initial VO2peak had the most changes after both training modes. However, like I said above, initial strength had no effect on how they responded.

Second, all "endurance" methods are not comparable nor do they necessarily cause an appreciable increase in mitochondrial count. Regardless of WHY someone has a "poor" response to endurance training, the fact remains that for whatever the reason they are clearly not deficient in that part of the equation relative to the other variables.

It therefore stands to reason, as I said previously, that if an individual is relatively more well-trained for endurance activities that strength training will have the most powerful effect on VO2 measures.

According to the results of this study, that is incorrect. The people were divided into quartiles of how well they responded to endurance training. In females, those that had the worst and best responses to endurance training also had the best responses to strength training. In males, the bottom two quartiles and and top quartile all had responses to strength training that were similar.

I JUST NOW took a look at the abstract. Here is a quote that 100% supports what I just said in my previous post. There is nothing to detract from it. I am glad I made that post before I looked, because it goes to show that I actually do have a fairly good understanding about what is going on in the body. Take a look.

"... the group with the lowest response to endurance training increased VO2peak after the resistance training intervention." The worst endurance responders were the best strength responders. Hmm. That's exactly what I said.

"The healthy males and females whose training response is low after endurance training seem to result in a marked improvement in their cardiorespiratory fitness by resistance training." That's the last sentence. This time they say, in plain English, exactly what I proposed.

I do know what I am talking about! :lol:

I'm afraid you don't. :P

That quote doesn't say that the lowest endurance responders had the best strength training response, it just says that strength training increased V02 in the lowest responders to endurance training. As I explained above, the lowest responders to endurance training DID NOT have the highest response to resistance training.

You may be right, as this is only one study, but this study does not support your thesis.

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Joshua Naterman

That is technically true, but as strength training is often something that endurance athletes neglect it is to be expected that anyone strength-deficient will benefit from strength training. Likewise, anyone who is severely deficient in their aerobic capacity (or perhaps more accurately their ability to handle anaerobic byproducts) will benefit from training that specifically addresses this concern. Another area, which is not mentioned at all in this study, is the total volume of blood flow per unit of time and the relative effort that takes the heart to perform. Increase in heart chamber size will allow more blood to be pumped per beat, which will increase an athlete's actual ability to move byproducts and probably to uptake oxygen as well since more freshly oxygenated blood cells would be moving at any one time. Of course, this study was far too short to show significant increases in that area.

Regardless, wherever you are MOST deficient is where you will see your best initial gains. If you noticed, A) the VO2Peak increases from strength gains were not presented as quartiles in the abstract and B) the gains in strength led to a lower average improvement than the endurance, yet the improvement was across the board. This too is to be expected, as strength takes much longer to build up than "endurance" due to the biochemical differences in the two processes. Myofibrils and myofilaments take longer to increase in quantity than mitochondria and capillaries for some reason.

From the introduction in the full text:

the purpose of this study was to test the

hypothesis that resistance training may increase VO2peak

in individuals whose responsiveness to endurance

training is low.

The only initial testing done was a VO2Peak test and an isometric leg strength test (done with a leg press dynanometer). I don't need to tell you that THAT is not a complete analysis of each person's relative ability in both strength and endurance. Without a complete analysis, it will be very difficult to figure out what is going on with each person as all hypotheses including my own would have to be reverse-engineered from the results and based on current understanding of how the different variables effect VO2Peak in relation to each other. I will say that from what I am reading, my assertations are pretty well upheld.

Endurance exercise training consisted of cycling on an

818E Monark cycle ergometer for 40 min (Stockholm,

Sweden). Each exercise session consisted of a 5-min

warm-up period (cycling at 50 and 75 W resistance for

females and males, respectively), followed by 30 min

of cycling at a resistance that elicited a HR of 70–80%

HRmax, and ended with a 5-min cool-down period

(cycling at 50 and 75 W resistance for females and

males, respectively).

Resistance exercise training was established based on

the recommendations of ACSM (Kraemer et al. 2002).

Resistance training consisted of 15 exercises involving

the major muscle groups performed with one set of 8–12

repetitions to near fatigue (8–12 RM). Each exercise

session consisted of a 5-min warm-up period (cycling at

50 and 75 W resistance for females and males, respectively),

followed by resistance training every 2 days

specifically focusing on either leg or arm strength. The

exercise session ended with a 5-min cool-down period

(cycling at 50 and 75 W resistance for females and

males, respectively). The first ten exercises included all

the major muscle groups, and the second half round of

exercises (5) mainly consisted of leg or arm exercises.

The velocity of muscle contraction was moderate, and

the resting period between the exercises was 1 min. At

the first two training sessions, the subjects were instructed

to use HUR strength training devices (HUR

Oy, Kokkola, Finland) and to find the correct resistance.

The subjects performed a single exercise set to near fatigue

even when the resistance was too low or high. If the

number of repetitions was under 8 or over 12 in a single

exercise, resistance was decreased or increased in the

next exercise session in order to reach 8–12 repetitions.

Now that, to me, was interesting. This was more similar to strength-endurance (anaerobic glycolysis) work than actual strength training. We still have little information for how subjects would respond to true strength training. As only the last 5 exercises were either arm or leg specific and switched each session, and as the VO2Peak test was done on the same implement (cycle ergometer) that was used for endurance training, I would say that there are some pretty serious confounds present in this study as far as external validity goes. I suppose it's reasonably good for bikers but that's about it. I am not sure why they would do full body work without focusing more on the legs on a regular basis, especially considering the low volume and infrequent nature of the leg work when it was done compared to the fact that machine biking is pretty much all in the legs. That's just a strange design to me. It would be very strange if the biking training session did NOT produce better results in the majority, which it did. These people were untrained bikers, and as they made neural adaptations to the bike their performance would improve. Biking is certainly more of a steady state activity than running, but it still has a strength component and that would increase as well during initial training. After all, they biked 5 days a week for two weeks. That's a lot of exposure. I suspect that a large factor in results, though certainly not the only large factor, was neural adaptation to cycling. The group that cycled more literally learned to be more efficient at cycling.

Furthermore, if you look at the tables in the study, the lowest endurance responders did have the best improvement from resistance training. The highest endurance responders did not have the worst strength gains, but were in fact not much lower than the lowest group. The intermediary groups are the lowest in effect size due to resistance training by far. I will suspect, but can not prove, that much of that has to do with recovery ability. We know that people exist on a wide spectrum of recovery ability, and also that the initial novice effects are quite variable from person to person. Because these are true novices, we can not be sure why this is happening. For a study to be more meaningful and insightful in this area, we need groups of intermediate level trainees. This may be difficult to gather a large sample for, but who knows? Maybe it can be done.

Regardless, much of what I said is upheld in the discussion section.

The main finding of this study is that if the training

response is low after endurance training, cardiorespiratory

fitness may be improved effectively by the resistance

training among the healthy male and female subjects.

There was no linear relationship between the responses

in VO2peak after endurance and resistance training,

suggesting that there are individual differences in the

training responses, which are highly dependent on the

training mode itself. Some individuals who are not able

to improve their fitness by endurance training seem to

obtain a marked benefit in their aerobic fitness by

resistance training. On the other hand, all individuals

who improve significantly their fitness by endurance

training do not necessarily benefit from resistance

training.

This, of course, overlooks an awful lot of things but that is to be expected. These are researchers and not professional trainers, and their knowledge sets are very different. If you notice the polarity, that those who do not respond to one seem to respond to the other, you will see a basic paraphrase of what I said initially. If you are not responding to endurance training you are most likely deficient in strength and will respond to resistance training, and visa versa. I just wish they had at least had a third group that specifically worked on muscular strength instead of a more strength-endurance approach. To me that would have been a very good addition, but I guess they were a bit limited in subjects. Still, they'd have had close to 30 in each group, which is what you need to very closely approximate the total population response to within 2%.

This, by the way, is a great discussion. Thank you, I am actually having fun!

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That is technically true, but as strength training is often something that endurance athletes neglect it is to be expected that anyone strength-deficient will benefit from strength training.

That's fine and I am not denying that strength training can help an endurance athlete. But I don't see the relevance to that and me thinking it is super cool and interesting that some people did not respond to endurance training but did to strength training.

Likewise, anyone who is severely deficient in their aerobic capacity (or perhaps more accurately their ability to handle anaerobic byproducts) will benefit from training that specifically addresses this concern.

No, not anyone. Every single person in this study was out of shape and had poor aerobic capacity yet not everyone responded to endurance training. In the discussion it mentions that other studies have found that about 10% of people are non-responders to endurance exercise.

Another area, which is not mentioned at all in this study, is the total volume of blood flow per unit of time and the relative effort that takes the heart to perform. Increase in heart chamber size will allow more blood to be pumped per beat, which will increase an athlete's actual ability to move byproducts and probably to uptake oxygen as well since more freshly oxygenated blood cells would be moving at any one time.

There are many things that go into a person increasing their aerobic capacity but I don't think it would be relevant to measure those things for this study as all the subjects were untrained and had low VO2peaks, so we can safely assume that they would be deficient in all those adaptations.

Regardless, wherever you are MOST deficient is where you will see your best initial gains.

Agreed.

If you noticed, ... B) the gains in strength led to a lower average improvement than the endurance, yet the improvement was across the board.

Yes, except in the 2nd highest quartile of men, but I would chalk this up as meaningless anomaly.

The only initial testing done was a VO2Peak test and an isometric leg strength test (done with a leg press dynanometer). I don't need to tell you that THAT is not a complete analysis of each person's relative ability in both strength and endurance.Without a complete analysis, it will be very difficult to figure out what is going on with each person as all hypotheses including my own would have to be reverse-engineered from the results and based on current understanding of how the different variables effect VO2Peak in relation to each other.

I don't see how any other tests, except genetic testing, would of given any insight, especially for endurance training. Since all the subjects presumably have poor aerobic and anaerobic adaptations, at least relative to their own genetic limits, the endurance training "should" of improved their VO2peaks. Since they all sucked aerobically, why didn't aerobic training cause adaptations that improved VO2peak? And in those individuals, why did strength training? Your assertion is that there is some macro-variable that explains it, but I think there is something genetic going on.

Now that, to me, was interesting. This was more similar to strength-endurance (anaerobic glycolysis) work than actual strength training. We still have little information for how subjects would respond to true strength training.

I don't think there would be any difference. The difference strength increase between 8-12 reps and lower reps in beginners over a 2 week period would be inconsequential.

I am not sure why they would do full body work without focusing more on the legs on a regular basis, especially considering the low volume and infrequent nature of the leg work when it was done compared to the fact that machine biking is pretty much all in the legs. That's just a strange design to me.

So why would a training protocol that focuses on legs (biking) in people who suck aerobically not cause an increase in VO2peak but a strength protocol which you feel is too infrequent on the legs would? You can't chalk it up to initial strength since strength was not correlated with improvement in VO2peak.

It would be very strange if the biking training session did NOT produce better results in the majority, which it did. These people were untrained bikers, and as they made neural adaptations to the bike their performance would improve. Biking is certainly more of a steady state activity than running, but it still has a strength component and that would increase as well during initial training. After all, they biked 5 days a week for two weeks. That's a lot of exposure. I suspect that a large factor in results, though certainly not the only large factor, was neural adaptation to cycling. The group that cycled more literally learned to be more efficient at cycling.

Agreed, but why would people who are doing training much more specific to the test not get any benefit but they do with training that is not specific? Again, you can't say that they had good aerobic adaptations already (they were all untrained) but low strength (no correlation with strength was found).

Furthermore, if you look at the tables in the study, the lowest endurance responders did have the best improvement from resistance training. The highest endurance responders did not have the worst strength gains, but were in fact not much lower than the lowest group. The intermediary groups are the lowest in effect size due to resistance training by far.

With the women I don't see any difference in response to resistance training between lowest and highest quartile. With men, the highest quartile had a slightly lower response, but if you converted it to absolute terms it would be very small, maybe 1 ml/kg/min or so.

Regardless, much of what I said is upheld in the discussion section.

"The main finding of this study is that if the training

response is low after endurance training, cardiorespiratory

fitness may be improved effectively by the resistance

training among the healthy male and female subjects.

There was no linear relationship between the responses

in VO2peak after endurance and resistance training,

suggesting that there are individual differences in the

training responses, which are highly dependent on the

training mode itself. Some individuals who are not able

to improve their fitness by endurance training seem to

obtain a marked benefit in their aerobic fitness by

resistance training. On the other hand, all individuals

who improve significantly their fitness by endurance

training do not necessarily benefit from resistance

training."

I don't see where that quote confirms what you said.

This, of course, overlooks an awful lot of things but that is to be expected. These are researchers and not professional trainers, and their knowledge sets are very different. If you notice the polarity, that those who do not respond to one seem to respond to the other, you will see a basic paraphrase of what I said initially. If you are not responding to endurance training you are most likely deficient in strength and will respond to resistance training, and visa versa.

Again, what results show that being deficient in strength will cause you to improve your VO2peak more than someone with more strength? From the study:

"There was no association between baseline

strengthpeak and DVO2peak after both endurance

(r=.01, P=ns) and resistance training (r=.04,

P=ns)."

This, by the way, is a great discussion. Thank you, I am actually having fun!

Yes, debates are great learning experiences! Unfortunately, I feel an irresistible pull from more important things to debating on the internet.

duty_calls.png

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Oh, I wanna play! (xkcd's what did it) Now, be patient, I've only begun my first semester in exercise physiology. Prior to that, I did my master's in counseling psychology, where actually learning seemed unrelated and maybe antithetical to the program.

Because the key element in improving VO2max is (usually?) stroke volume, could it be a cardiac pathology that explains why some people have more difficulty achieving VO2max benefits? What they call genetic could be uncontrolled for cardiomyopathy or other cardiorespiratory illness. In fact, by not controlling for cardiorespiratory illness (the only cardiac testing was a resting ECG), it's pretty much guaranteed that those WITH illness will cluster/tend towards one end of the data (in this case, towards least amount of adaptation).

Normally, we expect weakness in an area to predict greater adaptation, but in this case, it seems plausible that cardiovascular disease may obscure the results. I feel this analogy helps me clarify what I mean: a person who smokes cigarettes will induce cardiovascular damage. Their response to exercise may be more limited until the pathological arterial adaptation to smoking is overcome (which cannot be overcome in a mere two weeks). In this case, smokers may likely take longer to achieve certain adaptations. I am not stating this as a fact, merely as a possibility. A very superficial search for a comparative adaptation to exercise between smokers and nonsmokers gave me nothing.

My question after this study is this: Does resistance training improve VO2peak through stroke volume, cardiac output, or (most likely) (a-v)O2 difference (possibly due to effects of capillarization?)?

Oh, and feel free to tear my postulation to pieces. It's an amateur's attempt at understanding. :D

.sean

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Sean, if there were a problem with the subjects ability to pump blood it would of been exposed during the VO2 test. Their VO2 would of been very very low, like 20 or below, and they would of been excluded from the study.

On another note, can anyone get another study in full text? I can, but I have to make a special request that will take a week or two to get it. If anyone has full access now, I would love it if you could send it to me.

http://www.ncbi.nlm.nih.gov/pubmed/2113 ... t=Abstract

Int J Obes (Lond). 2010 Dec 7. [Epub ahead of print]

Adiposity attenuates muscle quality and the adaptive response to resistance

exercise in non-obese, healthy adults.

Peterson MD, Liu D, Gordish-Dressman H, Hubal MJ, Pistilli E, Angelopoulos TJ,

Clarkson PM, Moyna NM, Pescatello LS, Seip RL, Visich PS, Zoeller RF, Thompson

PD, Devaney JM, Hoffman EP, Gordon PM.

Laboratory for Physical Activity and Exercise Intervention Research, Department

of Physical Medicine and Rehabilitation, University of Michigan, Ann Arbor, MI,

USA.

Background:Emerging data have revealed a negative association between adiposity

and muscle quality (MQ). There is a lack of research to examine this interaction

among young, healthy individuals, and to evaluate the contribution of adiposity

to adaptation after resistance exercise (RE).Objective:The purpose of this

investigation was to examine the influence of subcutaneous adipose tissue (SAT)

on muscle function among non-obese individuals before and after

RE.Design:Analyses included 634 non-obese (body mass index <30 kg m(-2)) subjects

(253 males, 381 females; age=23.3±5.2 years). SAT and muscle mass (magnetic

resonance imaging-derived SAT and biceps muscle volume), isometric and dynamic

biceps strength, and MQ (strength/muscle volume), were analyzed at baseline and

after 12 weeks of unilateral RE.Results:At baseline, SAT was independently

associated with lower MQ for males (β=-0.55; P<0.01) and females (β=-0.45;

P<0.01), controlling for body mass and age. Adaptation to RE revealed a

significant negative association between SAT and changes for strength capacity

(β=-0.13; p=0.03) and MQ (β=-0.14; P<0.01) among males. No attenuation was

identified among females. Post-intervention SAT remained a negative predictor of

MQ for males and females (β=-0.47; P<0.01).Conclusions:The findings reveal that

SAT is a negative predictor of MQ among non-obese, healthy adults, and that after

12 weeks of progressive RE this association was not ameliorated. Data suggest

that SAT exerts a weak, negative influence on the adaptive response to strength

and MQ among males.

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Joshua Naterman

I have a big ol reply to our prior discussion that I haven't finished lol! Maybe I should just not post it, I dunno. It's pretty long I think.

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It's quite interesting there's a bunch of studies out there showing the anabolic effect of Omega-3's.

Post it if you like, but if its really that long then I just tap out. Can't go around and around forever.

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Joshua Naterman

LOL!!! I will see, I haven't looked at it in a few days.

It does seem that omega 3's can help up to a point, but it seems that when you use really high doses (like 30g per day) you actually start to see an inhibition of growth. That is not fully understood and I am not sure if that is just anecdotal or if there is any decent study backing that up. It is thought by the posters that I originally read this from that the omega 3's are actually inhibiting inflammatory processes that are a part of the growth process. I do not know if there is proof for this, but it is worth mentioning.

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This might be a neat study to look at. My uni doesn't have an online subscription to this journal though.

http://www.ncbi.nlm.nih.gov/pubmed/2115 ... t=Abstract

J Strength Cond Res. 2010 Dec 14. [Epub ahead of print]

An Electromyographical Comparison of Trunk Muscle Activity During Isometric Trunk

and Dynamic Strengthening Exercises.

Comfort P, Pearson SJ, Mather D.

Center for Health, Sport and Rehabilitation Sciences Research, University of

Salford, Manchester, United Kingdom.

Comfort, P, Pearson, SJ, and Mather, D. An electromyographical comparison of

trunk muscle activity during isometric trunk and dynamic strengthening exercises.

J Strength Cond Res 25(X): 000-000, 2010-The purpose of this study was to compare

rectus abdominis and erector spinae muscle activity during isometric (prone

bridge [PB] and superman [sM]) and dynamic strengthening exercises (back squat,

front squat [FS], and military press). Participants (n = 10, age 21.8 ± 2.6

years; body mass 82.65 ± 10.80 kg, 174.5± 7.2 cm), performed each exercise in a

randomized order, using a repeated-measures design. Electromyographical (EMG)

activity (sampling at 2,000 Hz) of the rectus abdominis (RA) and the erector

spinae (ES) muscles was recorded throughout the duration of the exercises.

Intraclass correlations demonstrated the highest levels of reliability for muscle

activity during the isometric exercises; however, all exercises demonstrated high

level of reliability (r = 0.764-0.998, p ≤ 0.01). The PB demonstrated

significantly greater (p < 0.01) RA activity compared to all other exercises. The

ES activity was significantly (p < 0.01) greater during the FS (1.010 ± 0.308

root mean square value [RMS (V)]) and SM (0.951 ± 0.217 RMS[V]) and compared to

all other exercises, although there was no significant difference (p > 0.05)

between the FS and the SM exercise. The PB may be the most suitable exercise for

strengthening the RA, compared to dynamic exercises at a low to moderate load,

because of a higher level of muscle activity. The FS may be a useful alternative

to isometric exercises when strengthening the ES, because it results in slightly

higher muscle activity levels when using only a light to moderate load. Because

of the dynamic nature of the FS, this may also be more beneficial in transferring

to activities of daily living and sporting environments.

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Was not familiar with term "prone bridge" before. Appears to be what is otherwise known as planck? Am I mistaken? Curious how it compares to the hollow hold...

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Yeah, it's the same thing as a plank.

+++++++++++++++++++++++++++++++++++

To all of you that are interested in research, I highly recommend this service that I just downloaded at http://www.mendeley.com/

I've been playing with it just now and it is AMAZING. It's a free service that allows you to keep track of all the research papers you read. You can open them right up in the program, sort them in categories, make highlights in the paper, add notes and probably lots of other stuff that I haven't discovered yet. You can also sync it up with your profile on the internet so that you can access your stuff from anywhere.

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Was not familiar with term "prone bridge" before. Appears to be what is otherwise known as planck? Am I mistaken? Curious how it compares to the hollow hold...

1746-1340-13-14-3-l.jpg

(I like the workout gear, it must be very bright in that office!)

Person experience shows that the hollow hold trumps plank. The arms, back and legs can still give considerable assistance in plank. While in a true hollow with lower back to the floor the arms and legs are unsupported, levered weight.

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