NATRC.org - Full Article
Greg Fellers, DVM, and Jamie Dieterich, Ph.D.
George Cardinet III, Bill Throgmorton and two other classmates from veterinary school, started research at the first NA
TRC ride at Mt. Diablo in 1961 to test George’s hypothesis that pulse and recovery rates were directly related to the horse’s physical conditioning. Not only did they find good correlation, their results showed that 12 minutes
of recovery gave the best correlation. That number was a nightmare to keep track of, and the 10-minute recovery became the standard allotted recovery period.
Since that time, pulse and respiration (P&R) recoveries after 10 minutes have been measured for 15 seconds, recorded, and scored according to guidelines set by the Judges Committee. Dr. Throgmorton considered a horse to have two different normal pulse readings: one at complete rest (28 to 40 bpm), and another at normal arousal (32 to 48 bpm). Thus for scoring, points have been deducted when the 15-second, 10-minute recovery count is over 12 (48 bpm)...
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