I am an outdoors runner. Although I haven't been doing much running lately, when I do go out I ensure that I am properly covered. I always wear a running skirt, I bring my Polar FT-60 along and of course I wear my running shoes - Nike Air Pegasus. I also wear sunscreen of at least an SPF 15 to protect my face. Even though I do have dark skin, it is important for me to keep it protected - believe it or not, my skin burns too!
I use a basic moisturizer with Sunscreen but since I sweat (not glisten) I have been considering using a waterproof moisturizer with SPF and La Roche-Posay Anthelios has an entire line of sunscreens with moisturizers that I may start using once my basic moisturizer runs out.
Even when I am not running outside, I keep my skin protected with sunscreen. I do everything I can to stay healthy and keeping my skin healthy is just as important as exercising my heart.