Endurance.Net Ridecamp Archives

Kat, excellent post (and for those on digest, I didn't trim it because it is worth re-reading).

 

Combine the physics and the physiology, and you begin to get an understanding of why winners of endurance rides come from all aspects of the weight spectrum (which is true in real life)--it just isn't that big a deal.

 

I would add another "variable" to the equation that impacts primarily heavyweights, but also heavy middleweights, etc.--and that is that there are many of us in the heavyweight division who shouldn't be, due to our own lack of fitness.  I speak from personal experience here....  I think I used Barry Waitte as an example before.  He is a "legitimate" heavyweight, in that he tacks in at around 220 and is fit as a fiddle.  His horse and my horse carry nearly the same static weight, but my horse is carrying an unfit human body that OUGHT to be in the lightweight division if it were fit.  Do you think that I impact my horse a whole lot more than Barry impacts his?  If so, then you'd be right.  And there are numerous people like me in the HW division who greatly impact the success of the division as a whole, despite the fact that fit riders like Barry can run right up front with ease.  But---our impact on our horse has next to nothing to do with our static weight--it has to do with all sorts of variables, some implied in kat's explanation and some not.

 

I'd add one more reason to kat's next-to-last paragraph as to why we have weight divisions--and it is so more people can "feel good" about their placing.  If you reduce the numbers against which you compete, your odds of "success" are much higher.  Heck, even in the shape I'm in, I'm often in the Top Ten heavyweights....   Sheesh.

 

Heidi

 

 

Bruce Weary said:

> I have a hard time understanding why people think
> horses are somehow magically exempt from the laws
> of physics, when it comes to carrying weight.

Probably because the people who are propounding about it have virtually
no understanding of (or if they do they forget to take it into account
intentionally to promote their personal agenda) the fact that the weight
of the rider is but one (and a fairly irrelevant one by comparison) of
the many variables that contribute to how much work a horse must do in
order to propel its entire load (i.e. not just the weight of the rider
and tack but the weight of the horse as well) forward down the trail.
And that how much work a horse must do in order to propel its entire
load down the trail is but one of the many variables that has an effect
on the outcome of the event.

Yes, physics says that, all other things being equal, there will be more
work performed with a heavier rider.  But since there is no way for all
the other things to be equal, the differences in rider weight pales in
significance. It is downright silly to handicap for just one of these
multitude of variables, especially since, by comparison to the other
variables, static rider weight is pretty insignificant.

> Why is a standard minimum weight often 165 lbs for some bigger rides?

Tevis USED to have this minimum weight requirement (probably because a
naive and short-sighted somebody thought "physics says that rider weight
ought to have an effect on outcome") until somebody else (Susan
Garlinghouse) did a controlled study attempting to correlate outcome
with rider weight and found that there was no correlation (although she
did find some correlation between the entire load and incidence of
lameness, which suggests that heavyweights may be inadvertently reducing
their chances of success by making the mistake of choosing a big horse).
While it is true that correlation does not necessarily imply causation,
it is also true that lack of correlation DOES imply lack of causation.

And, incidentally (and scads of data exist to support this), there is no
correlation in flat track TB horse racing between rider and tack weight
carried and outcome.  Race tracks around the country handicap races with
rider weight carried, because most people in the betting public are
foolish enough to think that weight carried has a big effect on the
outcome of the race, and if you want lots of people to bet on the
outcome of the race you need to get people to think that all the horses
might have a chance.

The other way that race tracks handicap races is by having horses run
"in their class" (and there are some pretty strict rules about this),
and since classifying horses (e.g. claimers, allowance, stakes horses,
etc.) takes into account all the other variables besides rider weight,
you would think that rider weight WOULD have a bigger effect on outcome,
but there is still no measurable effect (of course the variation in
weights is usually between 3 & 5 pounds, a fraction of the weight of
even the horse's breakfast, so only a fool would think that this might
have a measurable effect on the outcome).

> Could it be because anyone carrying less than that has an advantage?

Nope, it is because some people are foolish enough to think that anyone
carrying less than that has a measurable advantage because it seems like
it ought to, or because they never actually took enough physics to
realize that the mechanics of load bearing are far more complicated that
standing on a scale (and when you add movement into load bearing it
becomes even more complicated).

Chances are that many of the people who think this never took any
physics at all.  Since I vividly remember the first assignment in my
first quarter of high school physics  was a bridge building exercise
where everybody in the class was given the task of building a bridge
that spanned 8" (I think) to be made out of 55 of a specified brand
(don't ask me which one, it was over 20 years ago :)) of toothpicks and
Duco Cement (I do remember the brand of glue).  There were rules with
respect to how you could use the glue, etc. but the assignment was to
make a bridge that would hold up the most amount of weight (it was a
bridge design exercise, but it was also designed to get us thinking
about the effect of force vectors on load carrying).  Judgement day was
when we all brought our bridges into class, and each spanned them across
the gap between two desks set at 8" apart, stuck a metal rod through the
middle of it, hung a bucket off of it and kept adding weight until the
bridge failed.

The bridge that failed under the highest weight was able to support more
than FIVE times the load of the bridge that failed under the lowest
weight.  The difference in load carrying capacity of these bridges was
orders of magnitude, despite the fact that length and materials were
very strictly controlled for. Far more controlled for than the assorted
variables associated with the construction of the bridges (from a
mechanical physics standpoint, that is what a horse's back is) that are
our horses.  What I learned in all the subsequent physics (and
engineering) classes that I took is that, while the design and placement
of force vectors alone can have a huge impact on the ability to support
a static load, when you start introducing differences in materials and
size, etc. the ability to support a static load is impacted even more,
and that when the load becomes dynamic (i.e. moving) instead of static,
the ability to move that load is impacted yet again more.

People who think that the laws of physics say that the weight of the
rider must have a measurable effect on the outcome of an endurance ride
either never took physics or weren't paying attention during the first
week of their first class.

It isn't magic that the static weight of the rider and tack bears little
effect on the outcome of an endurance ride.  It is just that the
differences in static weight are so minor in comparison to all the other
variables that affect the outcome of an endurace ride that it gets lost
in the noise.

The reason we have weight divisions in endurance and that race tracks
have weight handicaps on flat track racing is that few people understand
the physics well enough to understand why rider weight has no measurable
effect on outcome, so they think it ought to.

If anybody who does understand it tried to really explain it (rather
than giving anecdotal stories from high school physics classes), most
people's eyes would glaze over with incomprehension because the physics
associated with how multilevered mechanisms move variable loads over
uneven terrain across time is EXTREMELY complicated and cannot, in any
reasonable way, be reduced to "have the riders stand on a scale."

kat
Orange County, Calif.



=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

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!!

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

 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!!

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=