If it is yoga or low impact like that? Target Champion bras will do.
Moderate to high impact? Lunaire Coolmax Underwire Sports Bra.
If it is anything with more impact? Enell! That's total boob armor.
Check
www.title9sports.com -- I like the barbell rating on the bras even though I do not like that they change the bra names. They carry the Lunaire but they call it something else -- the Wired And Ready For Action Sports Bra. The call the Enell the "The Last Resort Sports Bra."
A.