Osteoblast/Clast Remodeling VI: Implications

Can we dare say that most of our good feed throwing trainers are at least remotely aware of the osteoblast process. Probably when Mr./Ms. average trainer think of bone remodeling, osteoblasts are what is referred to. Everyone is (vaguely) aware that exercise stimulates bone remodeling and that this refers to "growth" or "strength". Thus each trainer produces this or that training formula believing it sufficient to do the job of bone growth/remodeling.

Looking at all of this much closer, we take note here that in fact equine bone remodeling is anything but what most people suppose. First, in the horse there is much more to it than mere osteoblast bone building. But, even if remodeling by osteoblasts were the complete process, if you understand that particular process you understand that it is woefully inadequate to the task. Why?

1. Osteoblast remodeling that produces "growth" of the cannon bone or any other bone has short term and long term limits:

a) short term, whatever new bone is produced, it will take two months to maturity, and even at maturity the new bone will be weak compared the old UNLESS the other remodeling processes are appropriately engaged.

b) long term because the cannon bone (and undoubtedly all bones) have growth limits. They only grow thicker to a point. We have seen on the blog that even in an extensively trained horse over many years, the overall cannon bone thickness is hardly greater than horses that have never seen a live race track. We do know the cannon bone also grows inward toward the medullary cavity (bone interior cavity), and that this growth greatly exceeds outward growth. Nevertheless, that growth will maximize and only produce "x" amount of additional strength. If we want more than X, i.e. if we want FR strength, we'll have to do more long term than rely on the osteoblasts.

The conclusion of all this is that with the limited purpose of calculating when our next speed work should occur to maintain FR we consider all the remodeling processes, but understand that the osteoblast process will fail to enter into this equation for two reasons: 1. it is a longer term and continual process instead of something that will be affected by our decision, e.g., to breeze every 3 days instead of every 8 days. 2. Even if we could maximize the osteoblast process the end product will be insufficient to achieve FR. We must engage the other remodeling processes to get FR.

Thus, after the race as I'm there on the back stretch gazing at my radiating cannon bones, and considering--what next-- what part does the osteoblast remodeling process play in my calculations? In the initial stages of training, probably quite a bit. The horse new to training must gain enough thickness at the appropriate places including under the periosteal membrane to withstand initial speed work. How long this takes is another discussion. BUT, after much appropriate training, and our horse being raced, at that point hopefully the increased thickness of bone produced by osteoblasts is mostly in place. Thus, post race, or post breeze, our horse will be unable to get a lot more than it already has from bone growth produced by osteoblasts. Again, the caveat and assumption of this blog--that you have an "appropriately" trained horse with all the connotations.

Training:

Mon. July 6:
Rod: Off
Art: Speed work: WU + 7f (some sub :14) + 2f slow.

Tues. July 7:
Rod: 2.7 miles mostly slow gallop (:21s).
Art: Off

Wed.
Rod: The force is with us (finally) as rain that falls in other parts of KC over last several days misses us. This was to be Rod's first official breezing over our back and forth farm course that has a 2.4 furlong distance were we can go full speed. We normally go back and forth in heats.
As Rod's first work in this pattern we hardly expected things to go smoothly, particularly with this horse. And, we were hardly disappointed. Nothing but trouble initially as the normally totally calm horse for reasons unknown decides to use this night to start spooking at deer. Imaginary, no less, almost losing Nob twice. At that point we abandoned "the course" and decided just to get the speed work in. Galloping in a familiar pattern Rod was all business, and we got in two 1/2 f spurts as warm ups and three 1.5 f spurts in probably :13.5s. Lazy Rod seems to have disappeared for now, as this horse continues to impress, knock on wood.
Art: 2.7 miles gallop in :20s. 2 heats: 1.8 miles + .9 miles. in prep for speed work tomorrow.