On With Bones

More than a year of bone posts and hopefully the blog has set out some basis for looking at FR. Per the February post I am ready to take the pictured collagen fibrils by the tail and sling them hard 240 consecutive times to simulate the horse foreleg striking the track surface during a race.

Can anything be learned from this concerning minimum frequency in getting and maintaining FR (fracture resistance)? Let's go at it, understanding in the image the blue are HA mineral platelets in various shapes and sizes and stages of development within a single collagen fibril, with the white being water, organic material, nucleus, mitochondria etc. These images are mature fibrils already primarily mineralized, as opposed to new borns that would lack the HA platelets.

We grab one end of this and sling. How much force to our effort? We will approximate that force with which the forleg strikes into the ground, but how much force is that? We have Tom Ivers' anomalous assertion of 12,000 lbs/square inch, yet, by our eyeballs is it really that much?

To get a true feel of how hard that "thud" is when hoof meets track in :22s probably you have to either be on the horse and feel the jarring that comes which each hoof strike at speed, or you need have a perfect camera angle to see the true force preferably in slow mo.

And, may I reiterate there is a marked difference in the amount of force as the horse increases speed. Somewhere between a horse doing 13 sec furlongs and :12s, the stride style transitions from ground flicking to ground pounding. This transition completes at :12.5 sec/ and force of what is now pounding increases with increasing speed into sub :12s, etc.

This attempts to convey that visually just looking at a race there appears to be far less force than there is. One ride on a horse at speed will quickly convince that this is optical illusion and that there's at least the equivalent force of a hammer striking the track surface somewhere between light and medium force with every single stride.

So, our "slinging" of the fibril is going to be fairly severe. I have equated this process with taking a half full 10 inch long oval canister of axle grease and slinging it hard 240 times. The grease inside the can will coagulate at one end and achieve probably it's near maximum density. With respect to a slinging a Type 1 Bone Collage Fibril in this same manner, we need take note of characteristics of the material compared to axle grease and then speculate on what may occur.

Training:

Left click to enlarge. This is our running paddock and shows the standing water ground conditions we've had in KC for the entire month of March for those times we had other than 6 inches of snow. This photo was taken 3/29 but this week we finally get some sun and wind, with rain holding off.

Mon. 3/29: This horse is going to kill somebody at the trot. Continually stumbles and falls on his face even over pristine surface. For Big Rod, impossible ground conditions. 10 min walk trot.

Tues. 3/30: Ground starts to improve a little, and able to do a little more trot. 15 min.

Wed. 3/31: 20 min walk trot. Ground is primarily dry but with egg carton ground conditions. pasture is going to require a lot of work to make our track gallopable.