I bought this bra because I am a 34 DD, and as such, it is very hard for me to find a good supporting bra, much less a good supporting sports bra that didn't make me jiggle all over the place.  I run alot because I am in the military so I purchased this bra because it was close to the same Champion sports bra that was issued to me in bootcamp, and let me tell you that thing worked wonders!  This bra not only gives you great support, it is also completely comfortable.  No squishing action to cause pain in breasts while exercising.  There is a slight giggle though, but im sure that there isn't a "perfect bra" that can hold you in with 100 percent giggle resistant and comfortable.  Great product!  so much so that I bought two!