Race Appropriate Fracture Resistance (FR): Conclusions

I guess I am ready to wrap this up, although there's a bit more thinking to do. Yet to be covered, definitely, the major concern of bone "de-training", whether there are any other remodeling processes besides the one already covered, and, to take an objective look at all the info and see if firm conclusions are really possible.

Recent major injuries cast yet a little more light: Musket Man, Pioneer Of The Nile. I'd viewed a few flaws in the training of Musket Man, although the video showed the trainer to be a young fellow with a head on his shoulders. Baffert I viewed as probably the most technically sound of this year's TC trainers, and he appeared to do a decent (as opposed to "perfect") job with POTN.

If the likes of POTN and Musket Man, who had better trainers than most of the TC horses, go down can we say this is "just racing"?

Readers of the blog know that I think otherwise. Injuries are eminent preventable although great care is required.

So, let's get on with it and finally figure out in the coming posts exactly what we need to do to keep our horse running--

Training

Thurs: 7/10
Rod: Off
Art: Speed work: WU + 5.5f in :13.5s. Strong work.
WU (warm up) was 2.5f + 1f +1.5f with last heat in :14s.

Fri. 7/11:
Art: Off
Rod: Weather related decision to go riderless due to humidity-- large, fat horse: Full speed riderless work: about 6 x 3f with full rests. By the time we started humidity lifted but too late to tack.

Sat. 7/12
Art: 2 miles riderless slow.--we decide to back off a bit as horse has twice in two days escaped the farm and spent 2 hrs. pacing after mares in a neighbor's paddock. Lost a lot of weight.
Rod: Off

Sun. 7/13 Off. Rain

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.

Osteoblast/Clast Remodeling V: What Stimulates The Process?

While on the subject of bricks I came across this. A mansion from Mission Hills , KC? No. It's Mary Arden's family home. Yes, that Mary Arden, the mother of William Shakespeare. Reminds of our present gaudy faux mansions of our good upper middle class. We've progressed less in 500 years perhaps than I'd supposed.

But, on to the business at hand. What to make of new bone produced by the osteoblasts that--according to this blog--has the same constituent nature regardless of the exercise load of its host.

Before getting to the implications of this, this post will cover some additional things we should understand about the process.

Four remodeling processes were described last post:

1. Bone glue changes.
2. Compactive changes in the mineral lattice.
3. Rearrangement of material.
4. Osteoblast/clast remodeling

Of these only osteoblast remodeling provides permanent changes as the other three processes are analyzed as temporary, in that unless reinforced by appropriate exercise their effects will disappear. And, as noted over several April posts, the above described temporary processes are stimulated only by appropriate speed work. Slow galloping e.g. will have zero effect on compacting the mineral lattice, etc.!

BUT, in all likelihood, osteoblast remodeling will be stimulated as much by the total volume of exercise, including the slow work, as by the speed of a race. Why is this so? The answer seems to be that the chemical--mechanical signaling which stimulates osteoblasts begins with any sort of exercise at all. Consider again the calf cannon photos:



The exercised calves were merely trotted a few minutes a day for (as I recall) 4 months.

Concluding then what we need to understand about osteoblast remodeling:

1. It occurs in response to any exercise including slow galloping.
2. The bone material produced as a result will take about 2 months to reach maturity.
3. Qualities of newly formed bone will be the same regardless of the intensity of exercise. New bone is of the same strength and molecular make up for our potato chip aficionado and our conditioned athlete.
4. While over the long haul adding new and additional bone to the cannon bone will geometrically strengthen that bone, over the short run the new bone will be weaker in the appropriately trained horse than the more mature bone tissue. By long haul I refer to 6 months to 2 years. The short run would mean from now till probably 4-6 months from now. Thus for the first 6 month of its existence, our new bone--unless acted on by the other remodeling processes, will be relatively weak!

Implications next post.

Training:
Mon. 7/6
Rod: Off
Art: Speed work. 2.2 miles total. .9 mile WU + 7f in :14s with sub :14 surges + 2f slow gallop.

Tues. 7/7:
Rod: 2.7 miles slow gallop--planned a nice smooth continuous and best gallop to date event. Result: the horse absolutely refuses to change any lead and has to be repeatedly brought to a trot to lead change, and then frequently refuses to get on the necessary diagonal. And, all this is complicated because the horse keeps stopping up on his breath starting up the next gallop. This one turned into a worst gallop to date fiasco. But felt a little better later when I remembered we'd simply never slow galloped this horse. Today was his first effort, and, responded as you might expect. First serious breezing on Wed.
Art: Off.

Wed: 7/8 Rod--we've planned 3 x 2f breeze work. Will be interesting how this first one turns out!

Osteoblast/Clast Remodeling IV: Brickwork

Hoping to understand "how often" our race horses "must" engage in speed work to maintain race appropriate fracture resistance (FR), the blog theorized the various bone remodeling "processes" in the race horse. Thus far these include:

1. Bone glue changes.
2. Compactive changes in the mineral lattice.
3. Rearrangement of material.
4. Osteoblast/clast remodeling.

#4 above is the present subject--osteoblasts and clasts-- with the question: what do they bring to the table in terms of bone remodeling and FR?

Consider again that equine bone might strengthen in several ways:

Circumference and size, inward and outward
Density
Strength and volume of bonding materials
Rearrangement and changes in quality and % of materials

What part do osteoblasts play regards the above? My conclusion (last post on this) had been that osteoblasts affect "bone size" or circumference instead of any of the other factors! If we may compare this process to laying bricks, can we say that regardless of what's under construction, or the form, shape and size the building will take, a brick is still a brick.

That's the theory, anyway. But, this has some logical support. Can we believe the osteoblast/clast bone construction process evolved over the eons, that the process probably is the same or similar in the fish, the dinosaur, modern homo sapiens, and our racing TBs. And, taking this further, the presumption is that the mechanical-chemical signaling/delivery devices that constitute this process are the same for the human couch potato as Usain Bolt setting a 100 meter world record. In the equine, we will fail to affect the process just because we race the horse.

Now, you shrewdly ask, is it conceivable that the continuing stress of athletic training might cause denser new osteoblast bone. We might e.g. due to the stimulus of exercise have more osteoblasts acting in a given area then in the couch potato. This is a legit question but decline going there for the following reason: If you take the trouble to read the exact chemical/physical processes involved in stimulating the osteoblast to act, delivering materials, forming the chemical and atomic bonds--somewhere in combing through such minuta I believe you'll persuade yourself that the material will be constructed in a certain pre-ordained way. Again, in this regard, while we may have more of them, a brick is still a brick.

Thus, for my purposes I will conclude that the osteoblast process will give us new bone material having a certain sameness to it's quality. This has significant implications--next post.

Our training, below.

Mon. Misc.

Training:
Sun. 7/5:
Art: prep for tomorrow's speed work: 2.7 miles 1/3 trot-2/3 gallop very slow.
Rod: Rare night when lazy Rod was hepped up. We decide on riderless speed work full speed 5 x 2f. Horse looked good. The idea was that hopefully the light bulb would come on in terms of speed and the tack work to come.

Mon 7/6:
Rod: Off
Art: Speed work. Last prior speed Nob had reported the horse weakened in the final 2f of the 7f work. Tonight the 7f went in :14s with some sub :14 surging. Nob reports definite wind up there on board. Strong all the way, unlike the last time. 2.2 miles total volume in 3 heats. A final 2f in :13.5 had been planned but was aborted as the 7f went faster then planned and was merely galloped.