As night fell in Canmore, Canada, in July 2008, Downey's Tinker Juarez was well on his way to his second straight 24 Hours of Adrenalin solo mountain-bike world championship when he was felled by his only real rival: a piece of mud. Suddenly unable to see, his eye painfully swelling shut when he tried to remove the grit, the 1996 Olympian was forced to withdraw while he still led the race. "I'll have clear-lens glasses on next time," he said later.
Sunglasses with interchangeable lenses -- full shades for bright sunlight, clear lenses for the dark and intermediate for in-between light -- are a must for long-distance runners, bikers, shooters and others who battle the elements day and night. The four lightweight models below all come with quick-switch frame designs and a variety of carry-along, coated lenses that'll protect your eyes from UV rays, bugs and mud at all hours.
-- Roy M. Wallack
Open and shut case
Oakley Jawbone: Unique pivoting-frame shades that Lance Armstrong wore in the Tour de France.
Likes: Easiest and fastest of the bunch to switch lenses, with less smudging. Two-step SwitchLock frame releases the lens when you pull the nose pads up with an audible click and pivot open the "jaw" (the bottom section of the frame), which is attached to the main frame by a hinge. You swap in the new polycarbonate lens with no pushing or pulling, and the lens is not subject to stresses that can bend it. Lens bag doubles as a lens cleaner and has a pocket for spare lenses. Choice of vented or non-vented lenses. Includes a pair of low-light yellow or persimmon lenses. A mix-and-match custom color option is $15.
Dislikes: The thick frame obstructs peripheral vision far more than others that lack lower-section frame members. And it ain't cheap.
Price: $195 to $225 (Armstrong's black-and-yellow model is $205). (800) 431-1439 or www.oakley.com.
Ryders VTX: Partially frameless minimalist design with three lenses.
Likes: No lower frame allows great lateral vision. Includes three sets of lenses: regular dark shades, clear (includes UV protection) and orange (for increased contrast in low light and forest conditions). Slight gap at top of lenses allows ventilation. Nose pads and temple arms can be bent and twisted for a custom fit. With a simple upward torque on the frame, notches in the lens easily snap out of and into the frame.
Dislikes: Bridge of frame sits so low that it is visible all the time, especially in the bent-over cycling position. Lens gets thoroughly smudged during the easy changing process. Spare lenses easily fall out of plastic lens sleeves; no fabric lens cleaner.
Price: $59. (800) 665-2903 or www.ryderseyewear.com.
Seeing is believing
Smith Sport Optics V90 Max: All-in-one frameless lens uses easily disengageable Pivlock snap-in temple arms to protect the lens. Two extra shields included.
Likes: Unobstructed field of vision since there is no frame; easily the best of the group. Easy to switch lenses: Pivot the temple arms up at a 45-degree angle to snap them out of the keyhole-pin interface, then squeeze the nosepiece and pull to remove. Includes clear and low-light red spare lenses.
Dislikes: The huge, double-length lenses don't fit well in packs and would seem to be more subject to damage than normal lenses. No plastic or fabric protective sleeves are included.
Price: $139. (208) 726-4477 or www.smithoptics.com.
Rudy Project Rydon: High-end system with five lenses and a minimalist frame.
Likes: Great frame-free peripheral vision and super fit because of nose piece and temple-arm adjustability. Four extra lenses in addition to standard dark brown: clear, yellow, red mirror and red-purple. Optional Impact-X polarized photochromic lenses are unbreakable and change with the lighting conditions (eliminating the need for extra lenses).
Dislikes: Out-of-this-world price tag; no special lens bag to carry the four spares in your pack.
Price: $275, plus $105 for optional polarized lenses. (888) 860-7597 or www.rudyprojectusa.com.
Cyclist and runner Wallack is co-author of "Bike for Life" and author of "Run for Life." email@example.com