I'm a 34D and this bra is about the only one I can wear that works well for me. http://www.teamestrogen.com/prodCW_165102.html (note: hope CWX aka Wacoal never stops making it, and TE never stops carrying it! lol... Wacoal is my only bra brand I can wear non-sports as well)

It also comes in an A/B version. The fabric is kinda a double system, but not foam padded cups. Also, I love a black sports bra the best. Black as a color does NOT turn see-thru when wet with sweat!

Besides my outdoor riding, I teach Spinning year round... lots outside riding-running guys in the front row of class this time of year... CWX black bra locked and loaded girls is how I face em for 60mins lol.

Good Luck with your search!

p.s. also, a print fabric helps to hide things as well... wear your solids when alone without boys, and busy print with if it helps your concern.