In brief:

Your bones are constantly remodeling. Cells called osteoclasts break down
bone and osteoblasts form new bone. In response to weight bearing exercise
(stress) on bone, the osteoblastic activity tends to dominate, forming
denser stronger bone. The same mechanisms are at work during bone growth and
bone healing after a fracture. A lifetime of weight-bearing exercise leads
to significantly denser bone that stays that way longer into old age.

Hope that helps,

Steve
----- Original Message -----
From: "Wally Day" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, January 08, 2001 5:16 PM
Subject: Re: [P-F] Calcium paradox.......


> Does anyone have an understanding of how and/or why
> weight bearing exercise can increase bone density? I
> understand how muscle mass in increased (damage to
> muscle cell, body repairs and overcompensates - a
> simplistic explanation), but that doesn't seem to
> relate to bones.
>
> I did a few searches, and the only "explanation" I
> could find is that exercise promotes mineralization in
> the bones. I'd like a little bit more enlightenment
> than that, if anyone knows....
>
>
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