Been on HRT for 3 ¹/₂ weeks and my chest/boobs are becoming extra sensitive... I just spent my day in a very cold A/c room (cold a/c due to unexpected rains) at work and I was freezing and I swear they were so sensitive I could not sit comfortably for even 2 seconds ... at the moment they are not that impressive (look like slightly large than normal man boobs      on me) and the weather is quite hot outside so I cant really wear thick clothes for too long ... so a bra can easily be seen through my thin clothes...  which could be very bad where I live....

Try wrapping one of those skin-coloured elastic bandages you use for sprains that you tie with a metallic thingie around your chest and cover your nipples. That way, rubbing should hurt less.

How about a compression shirt?  I wear one of those under my binder b/c my nipples have all of a sudden become sensitive.  It helps alot .. and it has an added bonus of a bit of warmth

Will try both out and see how it goes... thanx guys!! ... please let me know if anyone find any others as they would be very helpful!

Runners will put bandaids, etc over their nipples so they won't chafe.  That might work.

See if this helps...

http://running.about.com/od/illnessesandrunning/ss/embarrassing_7.htm

I did do an hour of heavy cardio at a local gym ... before going to work... but I am sure that the sensitivity started a few days before but was never this bad... thanx for link ... will be more careful as well! 

Try a sports bra with a properly fitting tank top to cover the straps.

Try a Stretch Sports Cami top.
Get a white one with wide straps. It we look like thick tee shirt but give you some support.

Jillieann