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[RC] Rider Weight - katswig@xxxxxxxxxxxxxTruman said: Bottom line is examples of "I saw a 350 pound rider riding a 14 hand Paso" has no meaning as to the ability of the population of horess (or Pasos for that matter) carry more than 15, 20, or 65 percent of their body weight. After all not many people ride horses that belong in the records books. One rat experiments only tells you want one rat did. Two rat experiements only tell you what two rats did and uncontrolled experiments are not any better as far as measuring properties of a population. Since it is individual horses that carry weight and not populations of horses that do, Truman, has, in fact, got this completely backwards. As is evidenced by Trumans's stated example of "I saw a 350 pound rider riding a 14 hand Paso," and his assertion that this doesn't mean that every horse (or even every Paso for that matter) can do the same, almost everybody should agree that there is huge variation among individual horses with respect to how much weight they have the ability to carry (begging the question entirely of exactly how "ability to carry" is being defined, which, BTW, is NOT an irrelevant question). Considering the fact that there is huge variation in the population, what percentage of its totally body weight, the "average" that the entire population can carry becomes almost totally irrelevant. With such huge variation (some horses are so badly put together and/or are already so lame that they don't have the ability to carry ANY additional weight so the percentage for them is 0%), one MUST look at the individual to determine what percentage of its body weight it can safely carry. It doesn't really matter what percentage of its body weight the other guy's horse can carry, nor does it matter what the average horse can carry. Making decisions based on averages is rarely ever a good idea; doing so when the variation in a population is so huge is absolutely nuts. The fact that there are examples of horses that have "safely carried" as much as 40% of their body weight for huge distances over long periods of time is not irrelevant. What it does is highlight the existence of the huge variation in the population so that people can understand that they had better look at their own horse rather than at some mythical "average" horse, since that horse doesn't exist. :) Or if it does, and we could find it, my horse probably isn't it. The second misnomer is there is really a "lightweight 250 pound rider." Two hundred fifty pounds is 250 pounds. Good saddles will help but still won't reduce the weight the horse is holding above the ground. The horse has to carry 250 pounds. The ability of the rider to ride balanced will help the horse - just as it will for a 100 pound rider - but it will not make the weight any less - the horse is still hold up 250 pounds. And this statement is pure hogwash. It only comes close to being true if the horse never moves (although the weight distributing effect of a saddle still has an effect, even on a stationary horse, since any structure is only as strong as its weakest link, if you distribute the weight that is put on each link, you have increased the ability to the entire structure to bear the load); however, since (I think) that when people ask "how much weight can my horse safely carry" are not asking how much weight they can put on their stationary horse, discussing static load is almost irrelevant (it is only relevant to the extent that static load affects the dynamic load, which also varies hugely). I SHOULDN'T need to explain to Truman the difference between a static load and a dynamic load (if I understand correctly, Truman is a physicist both by training and by profession so he understands the difference just fine); however, since most people on this list are not physicists (which I am not either, by training I am an engineer not a physicist), I will try to give a simple example (using a horse) to help people understand. Since almost everybody on this list is a horse person, most of them also know that when a horse canters (and when it trots if it is truly trotting), that there is a point of time during each stride when all four feet are off the ground (in horse parlance, this is called the moment of suspension). Obviously, when all four feet of the horse are off the ground, the horse is not "holding up" ANY weight, no matter how much it or its rider weighs; when the horse reaches to top of its arc (from having pushed up off the ground with its legs just before gravity brings it down), the horse and its load is "weightless." Equally as obviously, the horse cannot do this forever (which is why it is called a "moment" of suspension). When and how a horse comes down from its moment of suspension and how much force is exerted on the structures of the horse as it does so varies VERY much dependent upon how much momentum the horse has and in which directions, on where its feet are in relation to its center of gravity, and how it uses its own shock absorbers (i.e. its joints) to absorb and/or diffuse these forces..........(it depends on so many things they can't be listed). Not only does the ability to do this vary hugely from horse to horse (even horses of exactly the same static weight), depending upon its build and its experience, the ability of a rider (even riders of exactly the same static weight) to alter how the horse does this also varies hugely. There IS such a thing as a horse that is "light on its feet" and there is such a thing as a rider that is "light on a horse," and it has everything to do with how the horse carries its dynamic load and to what extent it can reduce its dynamic load by carrying it "better." And while the physics of it are EXTREMELY complicated (it is so complicated, in fact, that Physics 1A rarely ever goes into very much detail with respect to calculating dynamic loads), when talking about the loads on horses that are expected to carry the load forward (not just hold the load up), it is the only physics that is relevant. So, contrary to Truman's assertion, the examples of "I saw a 350 pound rider riding a 14 hand Paso" has a great deal of meaning. What one rat did tells you that you had better look at your rat and not the average rat (especially since nobody has even done a study to determine what the average rat can do). And contrary to Truman's assertion that "the ability of the rider...will not make the weight any less," the ability of the rider can have a substantial effect on how much weight a horse is carrying (and how much it varies during the course of every stride); although, I assert that this ability has less to do with "riding in balance" so that the rider's weight doesn't interfere with the way the horse carries its weight, and has much more to do with the ability of the rider to IMPROVE the way a horse carries its own weight. Good riders don't just stay out of their horse's way, they also affect the way the horse uses itself so that the horse itself becomes "lighter on its feet." And some of the ways to do this is to tell the horse where to put its feet and when and also to warn the horse in advance of any change it needs to make, so that the changes can be made more "smoothly." The bottom line is there is so much variation among both horses and riders (even horses and riders of exactly the same static weight) such that the question, "What percentage in static load of its body weight can the average horse carry?" is almost totally irrelevant. It varies between 0% and 50%. And one of the big reasons for this is that static load and dynamic load are only very loosely related (and are not perfectly correlated) to each other; and the higher the speeds, the looser this relationship gets. All of this also entirely begs the question of fuelling the effort over time. However, the ability to fuel the effort over time varies hugely from horse to horse. And how the effort is fueled over time varies depending on how much time we are talking about here (just how long is the effort? so in determining this we don't get to ignore the question of what is meant by ability). And if we try to evaluate the ability of a horse to fuel the effort over time, we can't even use the extremely complicated physics of calculating dynamic loads, we have to look at invisible metabolics. But make no mistake, a great deal of the calculation of a horse's ability to carry weight over time (even if that time is only the 2 minutes it takes to run the Kentucky Derby) is a function of that individual's ability to store fuel and to mobilize it for consumption during the effort. kat Orange County, Calif. -------------------------------------------------------------------- mail2web - Check your email from the web at http://mail2web.com/ . =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Ridecamp is a service of Endurance Net, http://www.endurance.net. Information, Policy, Disclaimer: http://www.endurance.net/Ridecamp Subscribe/Unsubscribe http://www.endurance.net/ridecamp/logon.asp Ride Long and Ride Safe!! =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
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