It is as easy to develop "vision-fitness" as it is to tone and strengthen other parts of the body. You can improve your vision through unique exercises, proper diet, and even by modifying your thought patterns, according to Dr. Robert-Michael Kaplan, author of Seeing Without Glasses and an international authority in vision training. Over 100 million Americans are nearsighted and at least six out of ten depend on glasses or contacts to correct their vision. Even those with healthy eyesight experience eyestrain from vision stress.