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Ant. wrote:

Wayfarer wrote:even astronauts use weights in space to keep up their bone density.

Osteoporosis takes years/decades to develop. How long are people in space for...?

What I'm getting at: they don't use weights in space with bone density in mind. Go find another false statement to back you up

weight bearing on joints is one of the main factors which keeps bone density up

Wayfarer wrote:

Ant. wrote:

Wayfarer wrote:even astronauts use weights in space to keep up their bone density.

Osteoporosis takes years/decades to develop. How long are people in space for...?

What I'm getting at: they don't use weights in space with bone density in mind. Go find another false statement to back you up

weight bearing on joints is one of the main factors which keeps bone density up

It's a factor, I'm well aware of that yes. I don't know if it's the main factor though.

What I was actually getting at is astronauts do resistance training in space for reasons other than bone density reasons (although that's not an unwanted side effect). Muscle maintenance would be it, for the obvious reason of needing to be able to walk when you're back on Earth and the other, maybe equally important reason - combatting orthostatic hypotension that they suffer after space flights. Way off topic though.


Personally, I'm going to carry on with my no weight bearing exercise and copious quantities of calcium ingestion (plus vitamin D goodness from sun). My body wants calcium; every athletes body wants more calcium compared to the average couch potato. I'm giving it an alternate source so it doesn't need to pluck it from my bones It's biologically plausible, so it satisfies me.

As far as I'm aware, no study has considered that, just because it'd probably be impossible to draw a population of athletes that don't do weight bearing exercise, with no other confounding factors and only looking at calcium intake over the past decade.

sogood wrote:Astronauts living for extended period in space have to do regular resistive exercises or they'll float away if they try to come back on land.

Come to think of it, this could be a cure for hypertension

Beta-blockers and ACE inhibitors are so last century

Ant. wrote:My body wants calcium; every athletes body wants more calcium compared to the average couch potato. I'm giving it an alternate source so it doesn't need to pluck it from my bones It's biologically plausible, so it satisfies me.

Well, I actually don't think this makes sense given what we know of the general principles by which the body operates.

Through negative feedback and other mechanisms, overdosing may induce a temporary benefit. But over time, it'll induce down regulation in the various systems to normalize the effective absorption and end effect At the end of the day, if the osteoclast and osteoblasts aren't getting the appropriate signals induced by stress and strain, then there will be resorption. We know this as bone remodelling to physical forces is a well documented. And even with impact training, there's an upper limit as to how far the bone would respond.

At the end of the day, it's a probability thing as shown by the percentage of study subjects who were noted to have the problem. So fingers crossed.

Ant. wrote:

sogood wrote:Astronauts living for extended period in space have to do regular resistive exercises or they'll float away if they try to come back on land.

Come to think of it, this could be a cure for hypertension
Beta-blockers and ACE inhibitors are so last century

Somehow I suspect PBS won't pay for this form of advanced treatment.

sogood wrote:

Ant. wrote:My body wants calcium; every athletes body wants more calcium compared to the average couch potato. I'm giving it an alternate source so it doesn't need to pluck it from my bones It's biologically plausible, so it satisfies me.

Well, I actually don't think this makes sense given what we know of the general principles by which the body operates.

Through negative feedback and other mechanisms, overdosing may induce a temporary benefit. But over time, it'll induce down regulation in the various systems to normalize the effective absorption and end effect At the end of the day, if the osteoclast and osteoblasts aren't getting the appropriate signals induced by stress and strain, then there will be resorption. We know this as bone remodelling to physical forces is a well documented. And even with impact training, there's an upper limit as to how far the bone would respond.

At the end of the day, it's a probability thing as shown by the percentage of study subjects who were noted to have the problem. So fingers crossed.

I don't think that stress and strain are the only signals that bring about positive bone remodelling, however I don't doubt that they're the most important. From memory, thyroxine, growth hormone also signal bone growth (which requires calcium which brings out parathyroid hormone) and maybe testosterone (but that one is a pure guess based on it's other anabolic activities), and they're all expressed after (and maybe during?) exercise. I know I'm not telling you anything new here
If there's more calcium available (not meaning plasma calcium obviously, meaning more ingested and more stored in the bones), then there won't be that net negative calcium deficit when everything is said and done.

What I should really search up on (ie, email a professor on the topic ), how beneficial is the effect of bone density of regularly consuming more than the RDI levels of calcium versus the 1000mg per day... how strong is the dose-response relationship, and can that be modified/increased some way?


Had never considered downregulation though May well come into effect, but even the type II people still benefit from exogenous insulin.

... but calcium is released around the bones because of resistance training. no real point in intaking it all if it just sits there most swimmers who get fractures do so when they kick off during a turn. this is due to low bone density, and the sudden shock through their legs causes a sudden fracture. it really is a good idea mate; they're implementing many resistance training programs in aged homes to keep bone density too..