That is the finding of a study in the Journal of Neuroscience. Exercise appears to preserve the structure and function of nerve cells in the retina after damage. 

Moderate aerobic exercise helps to preserve the structure and function of nerve cells in the retina after damage, according to an animal study appearing February 12 in TheJournal of Neuroscience. The findings suggest exercise may be able to slow the progression of retinal degenerative diseases.

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