I recently took up running.  One of the issues I've had in the past with high impact exercise was definitely finding a supportive bra for the DDs. (Currently a 36DD).  I love this bra so much I'm back to order another.  While the bra is pricey, Amazon seems to have certain colors on sale.  For around $28, I consider it a steal.  The thing I love most about this bra is that it does not create uniboob.  The girls are definitely separated, which makes the bra so much more comfortable than most other sports bras I own.  No more chafing as they rub together.  And once the bra is on, I basically forget it is there.  The shoulder straps don't rub or dig in, the underwire doesn't poke.  And the support is perfect.