I'm a big girl--40DD. I combine bras.

Before anyone jumps on me about the right sports bra being out there, believe me when I tell you I've spent countless hours (and not an insignificant amount of money) trying pretty much every sports bra I could find. I thought I had a winner with the Enell bulletproof vest model, but then I lost some weight and found myself in between sizes , where the smaller size was too tight around the ribcage to breathe and the larger was too loose around the top of the chest area to combat the bouncing--I think this has more to do with my own boob shape than any shortcomings of the bra...I still think it's a good bra, just not for me.

The combo I've settled on for the most comfort and support for me is a thin microfiber regular bra with a sports bra over it. The two that I use are the Microfiber Racerback from Fashion Bug (of all places) and the Champion C9 Cami from Target

I stumbled across that combo by accident, but it works for me. I'd actually worn the bra while out one day, then when changing at the gym didn't realize I'd forgotten to take it off and had just pulled the sports bra over it until part of the way through my workout when I realized I had no awareness of my boobs moving around. After that I tried it on the bike, then on my next run and was happy with the results. So, that's what I've stuck with. If it stops working, I'll go back to my search. But for now, I'm happy.