Re: warmup

[Tivers@aol.com]

In a message dated 12/12/98 3:43:14 AM Pacific Standard Time, Farafix@aol.com
writes:

<< he horse's pulse would run at a higher than normal rate until
 it was warmed up.  Interestingly, that was exactly what had happened at the
 beginning of that CTR. I noticed my mare running about 15-20 beats higher
than
 normal at the start  (I'd done that ride a few times before).  Typically, I
 about went into a mild panic since I didn't understand what was going on,
 slowed her to a jog on the flats, walked the downhill, in about 10-15 min she
 was running at a more normal rate.  We finished the ride with no problems.
>>

That early high heartrate artifact is tied to splenic contraction, I believe.
In a racehorse, it takes about 1/4 mile of all-out speed, or 2 1/2 miles of
easy lope, to cause the spleen to inject up to 50% of the animal's red cells
into the circulation. Thereafter, the HR settles to a genuine working HR. When
we test for Efficiency Score we have to wait for this to happen before we can
get an accurate figure.

ti