Thanks for that CW-X link. I took a look.
I was still hoping for something more light-weight with less fabric. But there really doesn't seem to be much out there.
I do a lot of my hiking in AZ, where it's hot, and the best sun protection is keeping your skin covered. So the lighter the fabric and the fewer "layers" I need to wear, the better (hence, the jealousy of my more petite collegues)...
I need support, but hiking isn't the same as, say horseback riding, where serious motion control and the "robust" support system of a sports bra is a must.
Thinking of what bugs me about regular bras for everyday wear, here are some of the things I came up with:
1) many of them have a slightly padded lining. Not tons, but enough to hold onto moisture.
2) all of them have underwires (pretty standard for bras in my size) - which is fine for every-day wear, but not something you'd want to sleep in, and which can get uncomfortable the hotter and wetter you get.
3) all of them have clasps in the back, and adjustment sliders, which can be irritating with the weight of a pack pressing against them - say going up-hill.
4) straps get pressed into your shoulders by your pack straps (potentially solvable with a racer-back strap setup)
I do have a few bras that are made out of a sort of mesh, which would at least solve issue 1) - but none of the rest.
On the face of things, a sports bra would address most, if not all of my complaints, but at the cost of a lot more fabric (which I need to cover with another layer to keep the sun off my skin) than what is strictly necessary to accomplish the task.
I was thinking something made like a triangular bikini top (not the string kind, but the kind that might have, say, a 1" wide, flat rib-cage band), that clasped in the front and had racer-back strap setup could work nicely. Strap adjusters could be moved to the front and off of my shoulder-blades (or, if I'm making it myself, just properly fit the straps in the first place and eliminate them entirely - along with extra fabric and fastener weight)...
And I could make it - if I knew what fabric to go hunting. Maybe just a light-weight un-lined lycra of some sort?
Any one more familiar with activity appropriate fabric that might be a good candidate?