She won a bronze medal in team dressage at the 1976 Summer Olympics in Montreal, aboard her chestnut gelding Keen, who she purchased, named, and trained herself.

She participated at the 1984 Summer Olympics in Los Angeles, again aboard Keen, where the US dressage team placed sixth.

[1] As noted, Gurney, at the pinnacle of her career, won a bronze medal in team dressage at the 1976 Summer Olympics in Montreal.

Hilda noted that training a horse for dressage was very difficult but very rewarding, despite the complexity and challenge of communicating with an animal.

She wanted spectators to know that dressage was physically demanding for both her and Keen, but needed to appear as an effortless, and aesthetically pleasing harmony between horse and rider.

After the 1979 Pan Am games, "Keen" injured ligaments in both front legs, and developed a spinal injury, but miraculously began recovering around 1982, and by 1984 was fit enough to compete again.

After graduation, she worked fourteen years as a teacher of educationally handicapped children, while continuing to compete as an Equestrian.