The Power of Imagery

mindtools.com

Imagery is the process by which you can create, modify or strengthen pathways important to the co-ordination of your muscles, by training purely within your mind. Imagination is the driving force of imagery.

Imagery rests on the important principle that you can exercise these parts of your brain with inputs from your imagination rather that from your senses: the parts of the brain that you train with imagery experience imagined and real inputs similarly, with the real inputs being merely more vividly experienced. So in its least effective form you can use imagery merely as a substitute for real practice to train the parts of your mind that it can reach.

Even at this inferior level of use imagery is useful training where:

An athlete is injured, and cannot train in any other way.
The correct equipment is not available, or practice is not possible for some other reason
Where rapid practice is needed However just to use imagery for the reasons above is to undervalue its effectiveness grossly.