Young horses might be easier to train if they temporarily lay off the sweets, according to a Montana State University (MSU) study that tracked behavior of 2-year-olds in training and compared it to their nutrition program.

The extra energy provided by sweet feed during the early stages of training made the horses in MSU’s study more disobedient and fearful than horses that only ate hay, said Jan Bowman, MS, PhD, an animal nutritionist at MSU.

The study involved 12 closely-related Quarter Horses that came from one Idaho ranch, Bowman said. Wade Black, instructor of the MSU Colt Starting class and one of Bowman’s graduate students, trained the horses for three weeks, five days a week at MSU’s Miller Livestock Pavilion. Half the horses ate only hay, which was a mixture of grass and alfalfa. The other horses ate five pounds of sweet grain a day in addition to the hay. Both groups ate as much hay and drank as much water as they wanted.

Each horse wore a pedometer adjusted to its stride and attached with an Ace bandage to its left front leg above the knee. They also had a combination wristwatch-heart monitor hanging from their saddles. The watch displayed minimum, maximum, and mean heart rates detected by an electrode belt