I ride my bicycle 7 miles every morning. When it's hot (this morning it was 81 degrees at 5:30am and over 90% humidity) I wear bike shorts, a sleeveless nylon running shirt, and a sports bra. Today, I had on a silver/grey shirt that normally hides the bra underneath. I usually do a fast-paced ride and there are some gentle hills on my route, so when it's hot I work up a pretty good sweat. Well, when the light grey shirt gets wet, it becomes a much darker grey. After my early morning ride this morning, I had a perfect outline of my bra on my shirt...front and back! Oops!