Where is the proof that 'Bone Conditioning' isn't BS?

[Matt Phillips]

I raise the point that since bone growth adolescent girls is maximal, any discrepancies in bone density would be further heightened.

Since bone growth/mineralization is at its peak while the bone is still growing, it is impossible for there to be any discrepancies to detect. Every healthy 17 year old girl is experiencing bone growth. The question here is whether a fully grown adult athelete can experience additional bone growth after the main growth phase has ended.

You're making too much of the age matching. the Athelete group had mean age 17.8 +/- 1.1, and the controls 17.9 +/- 0.6. They are all very close in age, and all in the group that is growing.

Anyway:
(1) Take a look at the boxer paper I cited earlier and
(2) Read the Jockey paper. You're jumping to conclusions.

[mkornecki]

I didn't say the assbone doesn't feel the impact, just that it's not the forces are sufficient to generate remodeling. Our asses get a lot of impact on a daily basis for even a normal person (not horseback riding), so you may not seen an effect compared to the boxer study, which is presents more abnormal forces requiring observable remodeling.

You are not arguing in good faith.

The difference in impact levels between horseback riding and normal day activities is certainly significant for an increase in bone density to occur, if compressive forces were the driving factor.

You casually dismiss a paper in a peer reviewed journal by bringing up points that they certainly were aware of and accounted for.

In general though, the reason I am getting vicious is that you are simply playing devil's advocate for the sake of being devil's advocate, without (seeming) to know the science behind what you are talking about.

No, rather it is simply because the vast amount of daily evidence seems to shows that low level compressive forces do not lead to an increase in bone density. Certainly not on the level required for the claims we are referring to. You habitually bring up studies that are related to an increase in growth, and other factors (not including the boxer article) forgetting that we are talking about denisty, that is, until I bring it up again.

No one has disagreed with you that tensile strength builds bone density. My position (I believe War Wheel's, but he can correct me if I am wrong) is that compressive forces also build bone density. Both types of forces build bone density (through altered bone remodeling) in an appreciable manner.

OK, what would you say is the relative effect of the two?

You seem to be rejecting compressive forces for no logical reason, despite the evidence to the contrary we have provided. This evidence includes:

1) The boxing study

Which I just saw and responded to as soon as I noticed it. You bringing this up in this manner again makes it appear that we have either been discussing this for some time now, or that I deliberatly ignored it. Neither is the case.

2) The pubmed articles I have provided about compressive forces driving bone remodeling (remember, remodeling leads to altered density--ie it's how it happens)

I addressed the abstracts that were raised.

Additionally, you try to draw analogies between muscle and bone without knowing the differing physiology between them.

As mentioned, I know the physiological differences. I bring up muscle because tensile forces are transferred to the bone via muscles and connective tissues. For you to be claiming that I think that muscle is the same as bone is another indication of bad faith.

In other words, I don't mind having a meaningful debate and argument, but at this point you keep saying "it's tensile not compressive" without providing any physics

*Noone* has provided any hardcore physics. If you think otherwise , you need to get a refresher course.

(which War Wheel) or articles (besides the Jockey article which doesn't speak to the type of force, and has a lot of issues with the group studied)

Are you writing that journals editor about their peer review process?

(that says compressive forces don't remodel bones. If you want to argue, great, just back it up with some science.

Are you saying that bone remodelling ALWAYS leads to an increase in bone density that is greater than average...?

I doubt you are.

But regardless, I have to go now. I will respond tomorrow. Please don't accuse me of intentionally ignoring your posts.

[mkornecki]

Since bone growth/mineralization is at its peak while the bone is still growing, it is impossible for there to be any discrepancies to detect. Every healthy 17 year old girl is experiencing bone growth.

OK, last one for today, I promise.

You are seriously suggesting that ANY bone density testing study is invalid if it involves adolescent girls? To make such a claim, with the additional implication that you are aware of this, and the journal editors and referrees are not, is preposterous.

The question here is whether a fully grown adult athelete can experience additional bone growth after the main growth phase has ended.

Which does refute the significane of the adolescent study.

You're making too much of the age matching. the Athelete group had mean age 17.8 +/- 1.1, and the controls 17.9 +/- 0.6. They are all very close in age, and all in the group that is growing..

Exactly, which reinforces the theclaim that age factors are statistically removed.

Can't get past the abstracts. My government site does not sem to have access.

[SifuJason]

You are not arguing in good faith.

The difference in impact levels between horseback riding and normal day activities is certainly significant for an increase in bone density to occur, if compressive forces were the driving factor.

You casually dismiss a paper in a peer reviewed journal by bringing up points that they certainly were aware of and accounted for.

I didn't casually dismiss it, I analyzed it, just like War Wheel did. As any scientist knows, a lot of stuff gets published that has serious flaws. In this case, the flaw is that the study deals with growing women, which may confound any observations seen.

No, rather it is simply because the vast amount of daily evidence seems to shows that low level compressive forces do not lead to an increase in bone density. Certainly not on the level required for the claims we are referring to. You habitually bring up studies that are related to an increase in growth, and other factors (not including the boxer article) forgetting that we are talking about denisty, that is, until I bring it up again.

What daily evidence are you referring to? Both 0-gravity and martial arts (which have significant differences in compressive forces from the norm) show altered bone density. Seems to me the evidence indicates bone density is altered by compressive forces. "low level" of any force may not alter bone density, since your bones don't need to adapt to such "low levels" of force, as they are already sufficient. Similarly, your hip may be already sufficiently dense to deal with horseback riding, while you arm needs reinforcement to deal with the impact of boxing and your spine the compressive forces of judo.

OK, what would you say is the relative effect of the two?

I can't really make an educated guess, other than to say "whatever your bone needs to compensate for, given the stresses you are placing on it repeatedly over time.

I addressed the abstracts that were raised.

Not with any depth or clarify of scientific thought, which is my issue. (see below)

As mentioned, I know the physiological differences. I bring up muscle because tensile forces are transferred to the bone via muscles and connective tissues. For you to be claiming that I think that muscle is the same as bone is another indication of bad faith.

At this point I feel you should disclose your education level, like War Wheel and I have. I am not arguing in bad faith. You said you think it is reasonable to assume bone and muscle respond to stresses the same way, and I say that based on what is known about them, it makes perfect sense that you can't assume since muscle doesn't "strengthen" in response to compressive forces, that bone won't. It just doesn't make sense.

*Noone* has provided any hardcore physics. If you think otherwise , you need to get a refresher course.

I don't believe I said hardcore. I simply said he provided some physics at a basic level to describe how gravity does indeed generate compressive forces (since your bones are compressed by the weight of the tissues they hold up).

Are you writing that journals editor about their peer review process?

Again, no need. I don't take everything at face value in any peer review journal. I read the articles and evaluate the studies for flaws. Most papers have flaws, some are fatal, some aren't. It's the nature of science.

Are you saying that bone remodelling ALWAYS leads to an increase in bone density that is greater than average...?

Here is my logic train. Changes in bone density are a result of bone remodeling in response to continued strain on the bone. For changes in density to occur, bone has to be remodeled. Compressive forces are shown to affect bone remodeling. Forces are on bone are known to alter bone density over time. Thus, compressive forces, which can alter bone remodeling, will alter bone density over time. You have been arguing that bone doesn't respond to compressive forces, which has been shown to be incorrect.

[SifuJason]

OK, last one for today, I promise.

You are seriously suggesting that ANY bone density testing study is invalid if it involves adolescent girls? To make such a claim, with the additional implication that you are aware of this, and the journal editors and referrees are not, is preposterous.

They can be aware of it, and publish it anyway. Happens all the time.

[Jim_Jude]

Gravity produces loads that result in tensile forces on bone and muscle.

Put your forearm on the table in a manner similiar to an armwrestling position, but perfectly vertical. Make a fist and balance a 10lb weight on it. Do you think in 10 years, the muscles and bones in the forearm will be bigger? denser? Or will they have been atrophied due to lack of tensile load?

My vote is on the latter.

I can't think of a high school graduate who wouldn't agree with you. Fuckit, let's lower the bar to GEDs, or maybe Jr High grads.

[Dsimon3387]

Read what I wrote again. You're getting me exactly backwards. And not in a good way.

Ok. my mistake.

[SifuJason]

I can't think of a high school graduate who wouldn't agree with you. Fuckit, let's lower the bar to GEDs, or maybe Jr High grads.

Obviously, you do not appreciate nuanced, technical thought. No one is arguing that tensile forces affect bone density. The question is do compressive forces also affect bone density. (the answer being yes). Read the whole thread before commenting next time.

[Matt Phillips]

OK, last one for today, I promise.

You are seriously suggesting that ANY bone density testing study is invalid if it involves adolescent girls? To make such a claim, with the additional implication that you are aware of this, and the journal editors and referrees are not, is preposterous.

Why is that preposterous? If I were a reviewer on that article, I would have asked them to respond to that objection.

Can I get a response to the reasoning instead of an appeal to the infallability of peer review? FTR, to my knowledge I am the only person posting on this thread that has published any research dealing with bone biology. Notice I didn't menton it? Appeals to authority are weak IMO.

Which does refute the significane of the adolescent study.

I think so, yes.

Exactly, which reinforces the theclaim that age factors are statistically removed.

One of us is being a bonehead. Maybe its me. Let me restate my position one more time in the hope that it is not me:

All of these girls are about the same age;
All of these girls are still growing;
The amount of mineralization, remodeling, and growth in a bone is at its peak during growth; It can't remodel any faster no matter how much you stress it;
This study is fatally flawed for that reason. The fact that it was published does not remove my objection. Only an argument can do that.

Your ball.

Can't get past the abstracts. My government site does not sem to have access.

Mods: Is there a possibility of uploading papers to the site? Can we have a fight science forum?

[Jim_Jude]

Obviously, you do not appreciate nuanced, technical thought. No one is arguing that tensile forces affect bone density. The question is do compressive forces also affect bone density. (the answer being yes). Read the whole thread before commenting next time.

LOL. yeah, okay.