Sent: Wednesday, October 03, 2001 5:11
PM
Subject: RC: a nickel tour of gait
biomechanics
I've
also read someplace that some horses operate at a lower heart rate at a trot
and some do at a canter. I've also heard that the extended trot is also
hard on the horse biomechanically.
This
is worth a comment, only because I was lucky enough to do some research under
a biomechanal physiologist that's been doing work on preferred gaits in horses
for decades. The gist of the research spells out that within each gait,
there's a preferred speed unique to each individual horse based on his
conformation, size, joint integrity (ie, presence or absence of painful things
like arthritis) and efficiency of the cardiovascular system. Most riders
already know intuitively that when they've ridden their horse for enough miles
at a consistent speed over consistent ground, the horse tends to drop into a
'groove'. You can slow this speed down or extend it upwards, but left to
his own devices, an experienced horse drifts back into this groove.
Right? What Dr. Hoyt demonstrated in numerous species is that this
preferred speed within each gait is *also* the speed at which the entire
system is moving most efficiently, based on oxygen consumption, joint strain,
concussion and so on. It's kind of a package deal. If you force
the horse to travel at either above or below this preferred speed, then
efficiency decreases in one way or another; and if you stretch that gait too
far beyond the preferred speed, then usually the horse is going to want to
'shift gears' into either a higher or lower gear---that is, if a horse's
preferred and most efficient trotting speed was 10 mph, but you forced him to
extend that trot to 14 mph, then his natural preference for an efficient gait
is going to make him want to break into a canter, so that he can try to drift
towards the preferred groove of the canter. A lot of riders here have
noticed that heart rate will drop when their horse shifts gears, and that's
just what Dr. Hoyt's research has observed---that an extended/force trot is
not necessarily a more efficient gait than cantering 'in the groove' (don't
bother with the jokes about being in the groove, we've tortured poor Dr. Hoyt
with all of them)<g>.
Anyway, one of the other things that he found out is that this
preferred speed within gaits doesn't just apply to horses, but to almost all
of the quadraped species and most of the bipeds as well. The only
species it didn't apply to was elephants, because they only *have* one gait (a
walk).
I
hope this helps, but probably just hopelessly confused everyone. Oh,
well.
Susan G