The entire concept of eye exercises has been shrouded in mystery by various authors. Various advantages are attributed to exercises. This section is designed to throw light on this fascinating subject.

Before proceeding to details of eye muscle exercises, it is necessary for us to know what are we exercising, the muscles involved and why.

How many muscles are there in an eye?

There are six muscles outside the eyeball and one muscle inside the eyeball.

What do the external (outside) muscles of the eye do? What are they used for?

The eyeball is kept in the desired position, and turned from place to place, by the use of six muscles. These muscles are identically placed in both eyes to permit synchronous movement. There are essentially four muscles, termed rectus (Latin for straight) muscles, which by their actions move the eyes up or down (the superior and inferior rectus), outwards towards the temple or inwards towards the nose (lateral and medial rectus). There are also two oblique muscles which move the eye in oblique directions called the superior and inferior oblique muscle.

The movements of the two eyeballs in the cardinal directions require the muscles of both eyes working together. Thus the medial rectus (which turns the eye in) of one must work together with the lateral rectus (which turns the eye out) of the other to permit the eyes to move simultaneously. These conjoint muscle actions thus label them yoke muscles (like two bullocks who move together if they are on a common yoke).

The above elucidation has been made because exercising uses "yoke" movement. It is thus not possible to exercise an eye separate from its fellow and all exercises are designed with this in mind. Thus there are two sets of movements.

(1) Conjugate movement (Latin: con=with; jugate=yoke)

In this both eyes move together, keeping their visual axes parallel (thus movement left-right, up-down or even obliquely up-down are labelled conjugate movements).

(2) Dysjugate movement (Latin: dys=bad)

Looking at a near object or convergence requires the two eyes to bend in. To straighten again, they have to shift out to take up a parallel position (divergence).

Thus, a completely different set of exercises are needed for dysjugate movements.

What does the internal muscle of the eyeball do?

There is a muscle inside the eyeball called the ciliary muscle. The ciliary muscle is circular and controls the shape of the lens inside the eye. A person changing from looking at a distance to near is, in essence, increasing the power of his lens to focus for near. This change in focusing power is termed accommodation, and is controlled by the ciliary muscle.

Hence all exercises for the ciliary muscle are designed to shift focus from distance to a near point.

As a person grows older, or under circumstances of poor health, or even in medication with atropine-based products (normally used for stomach cramps and to decrease gut mobility) the ability of the eye to focus grows poor, requiring additional plus lenses to compensate for the weak ciliary muscle. This condition is called presbyopia.

Dustin Flores

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