Colorado is one of the world's most beautiful places to live, but our high altitude subjects our eyes to more ultraviolet rays and puts us at much higher risk for a sight-threatening condition called macular degeneration. This article from my website talks about UV and other reasons to wear good sunglasses.
Using good, high-quality sunglasses is a very good way to protect your eyes from damaging UV rays. My eye doctor, Dr. John Rabins is the man to see for an exceptional eye exam, and for proper sunglasses. He can even make prescription sunglasses to suit your sports needs, such as skiing and other outdoor recreational activities.
Please feel free to contact Dr. John, and tell him I recommended you. He'll take great care of your eyes!