I have some ideas on sports sunglasses, made specifically for the adventure racers. They would be used by rock climbers, eco-challengers, obstacle coursers, etc. They are somewhat like goggles, except without the tight feeling around the head. The tightness could be adjusted just before entering any water. The lenses have a UV protection agent to them. Draw-back - wear and tear. Due to the type of sport done, the sun glasses may not make but one trip, but then what sunglasses make...