Icelandic Horse: Ancient breed of horse originating in Iceland. Known as versatile riding horses, exhibiting a unique gait, the tolt, or running walk.
Impulsion: Strong but controlled forward movement in the horse (not to be confused with speed)
Inbreeding: The mating of brother/sister, sire/daughter, son/dam, to fix or accentuate a particular trait or character.
Indirect Rein: The opposite rein to the direction in which the horse is moving. When giving an indirect rein aid, the instruction comes by pressing the opposite rein against the horse's neck.
In Front of the Bit: A term used to describe a horse which pulls or hangs heavily on the rider's hand.
In Hand: When a horse is controlled from the ground rather than being ridden.
Inside Leg : The legs of horse and rider which are on the inside of any circle or curved track being travelled.
Irish Draught Horse: Breed of draught/draft horse originating in Ireland. Popular for crossing with lighter breeds to produce the Irish Sport Horse.
Irons: The metal pieces attached to the saddle by means of leather straps in which the rider places his feet. (See also Stirrups)