Re: Big bone vs small bone

[Tivers@aol.com]

In a message dated 98-06-25 21:56:47 EDT, CMKSAGEHIL@aol.com writes:

<< << Your intuition is incorrect. Bone density can decrease as much as 30%
 during the remodeling process. >>
 
 No, Tom, I am not talking about the remodeling period.  If you reread my
post,
 I believe I mentioned that this change occurs over YEARS.  If I didn't, that
 is the time frame of my observations.  What I have been told by the people
who
 research bones is that the decrease in density actually takes more like 4-6
 weeks, rather than the 2-3 weeks you mention, with another 4-6 weeks before
 the bone is even as strong as it started out. >

Depends entirely on the magnitude of the initial insult. Small decrements in
density are repaird within 5 days after the work that caused them. I've seen a
loss of 20% cannon bone density after a single, inappropriate 2yo QH breeze at
1/4 mile. In a week, half that density was back, and in another 2 weeks, the
bone was back to where it was to start with. 


> The additional strength begins
 to occur after that--nearly three months into training.>

That's Potter's work. He was watching QH trainers cripple their horses by
banging them against speed at max effort every five days. Not enough repair
time--bone gets worse and worse. then Potter recommends a period of light work
so that the bone can spring back to health--usually this is enforced with
bucked shins and firing or blistering. The whole process is stupid, from
beginning to end.

>  My numbers on cannon
 circumference are from pre-training to old campaigner--for instance, one of
my
 stallions had 8-1/2" cannon circumference at 6 and had increased to 9+ inches
 at 14, when I said to myself, gee, his legs look bigger, maybe it would be
 interesting to remeasure him.  Have talked to many other riders since who
 measured their horses early in their careers, and they have gone back and
 remeasured and found the same thing. >

There is no doubt that exercise will increase bone density and dimensions--but
most of the modeling is over after age 3. Remodeling changes the shape of the
bone and may add some extra dimension, but mostly it's additional density.
 
 Heidi>

ti
  >>