Looking at the floor also provides the eye with a fixed position reference. Any deviation from the correct movement pattern can be identified easily against this reference and can be adjusted as it happens. The ceiling also provides a reference, but at the expense of an unsafe neck position. And, generally speaking, the floor is closer to the eyes than the ceiling, and is therefore more useful as a reference — smaller movements can be detected against a closer point. To correct looking up, fix the eyes on a position on the floor five or six feet in front of you, or if training close to a wall, on a place low on the wall that results in the same neck position. Stare at this point, and get used to looking at it so that it requires no conscious effort. Most people will not raise their heads to the point where neck position is affected if they are looking down. Inventive coaches have used tennis balls for the purpose of illustrating a
chin-down chest-up position