When Endurance came to me, it was in its infancy. We had no idea how far a horse could go or how fast. We did not want to be like the Pony Express and run horses to death.

Long distance riding started with Competitive Trail Rides, where a horse’s speed was limited to 6 or 7 mph for 30-40 miles. Veterinarians were our judges. Pulse recoveries were 10 minutes. Distances went to 50 miles, 75, and then a few great 100-mile rides. Statistics on each horse ‒ those that didn’t finish and those that did finish ‒ were carefully recorded. Helicopters were flying overhead at an Old Dominion ride, taking tired horse blood to the vet school in Athens, Georgia, for analysis.

What was discovered was that pulse recovery was paramount. Dehydration and colic were the enemy. The 10-minute pulse recovery was then used in Eventing, but Endurance horses, with the long distance, needed food and water and more rest time. An actual pulse requirement was established; the first was 72 beats per minute, followed by a 30-minute hold. The time limit was 24 hours to complete a 100-mile ride, which included the holds which were found to be around three hours of hold time.

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