Proper conditioning is a very important factor in getting the most out of a competition horse. There are two elements to fitness—cardiovascular and musculoskeletal. They are equally important. Both are ideally developed through long slow distance work (LSD).

About halfway through my 2009 Florida high-goal season, Hale Bopp came up lame. At the time she was 17. Our team’s veterinarian assessed her, found degenerative changes in one front ankle, suggested injecting that joint with hyaluronic acid and cortisone, and said she’d be ready to go for our nex...