The use of mental imagery appear to be a powerful rehearsal strategy for learning motor skills. As such , it can also be an effective instructional strategy. For example, rather than provide the arm movements to perform a side stroke in swimming, the instructor can provide the students with a useful image to use while practicing the stroke. The image given the students is of themselves picking an apple from a tree with one hand, bringing the apple down , and putting the apple in a basket. The remembering of the sidestroke is enhanced by changing the abstract, complex components involved in the skill into a concrete, meaningful movement.