Bones and Warming Up: Conclusions

Last warm up-fracture resistance post 7/20, then major side track. But, now, drum roll please, as I'm ready to make whatever conclusions are possible given the paucity of research.

The question was whether the manner of warming up the horse makes any difference in terms of fracture-resistance of bone material during the race? This has yet to be answered and so we're left with speculation based on available information.

Others way before me have considered the question. I found an article dated 1967 were the scientists documented the "shaking up" of bone material as movement and stress commences. I also believe there is enough on the Paul Hansma website from UC Santa Barbara Department of Physics to indicated definite changes in bone under stress compared to bone at rest. The UCSB studies are at the atomic and cellular level. I've included several of the atomic force microscopy images in the earlier posts that clearly show changes in the bonding process as stress on the bone commences. The key illustration in this is this one (left click to enlarge):

Looking at this image of the protein based "bone glue", the problem I have in concluding absolutely that there is any sort of preparatory or girding process against additional force is that the "sacrificial bonds" discovered by the Hansma group and illustrated above can be seen to merely lengthen with the onset of stress. So, does this mean that with the onset of stress each bond is then stronger than at the relaxed position above "before impact"?

One would presume so. I think you have to presume this that with the change in millions (I'm also presuming that number) of organic bonds covering and surrounding the type 1 collagen fibrils which surround the mineralized portion of the bone matrix that there is a girding effect.

Interestingly, in my own hand clapping experiments (see my July 12 post) I could feel this girding effect in my wrist bones as I continued hard claps, BUT, the girding seemed to be more effective after some initial clapping and a five minute rest. When I recommenced clapping after the five minute rest period my wrist bones seemed much more accommodated to the force than during the initial clapping. In other words when you start clapping your wrists together I did not after a series of 10 claps feel increased resistance on the 11th clap. It seemed that "girding" was related to both the amount of force applied and also the time period that elapsed from the commencement of the clapping.

Thus I believe that the amount of force applied in the warm up is important but so would be some time lapse to the application of greater force. Luckily in equine warm ups we do have this luxury of time because between the initial warm up there is the lengthy walk to post which does allow the time to lapse.

So, I am prepared to believe that exposing equine leg bones to more concussion than merely trotting or slow pony assisted cantering or galloping would significantly increase the fracture resistance of the bone material during the race. Relying on the initial strides of the race itself to "shake up" the bones and provide the resistance is insufficient due to lack of time lapse.

Leave it at that for now, and I'll get to the overall conclusions on appropriate warm up in the next posts.

Training:
8/13 Groovin' Wind: Farm breeze 4 x 2.4f with only the middle furlong of each heat at max speed. The rest of each 2.4f was gallop in and out of the speed. Horse very energetic, strong and willing. We'll repeat 48 hours later and hopefully on to Eureka Saturday.

Art:
8/11/07 Sat. Day 1 Burch: 10 min under tack walking, attempt trot.
8/12/07 Sun. Day 2 Burch: 1 mile W/U and 1 mile riderless at about :16/f. 10 min walk under tack, the first extended trot.
8/13/07 Mon. Day 3 Burch: 4 x 1f heats riderless at full speed. Horse was driven into the speed and maintained it over each furlong. This was preceded by appropriate warm up heats. Skipped tack work as we'd been under tack five straight days before.