One of the drawbacks that tend to have some women to perform physical activity is the movement of her breasts which, apart from being annoying and even painful, accelerates the break of the fibers that hold them. This problem can be solved to a large extent with a good sports bra, designed and built specifically to support the characteristics of sports.
A good sports bra should be able to reduce much of the movement generated by the chest when it comes to a sport, provide comfort, not make scratches and have the ability to perspire.
In the web of Shock Absorber, you can see according to the sport you to practise several simulations of the movement of the breast without BRA, with one normal and one sports bra for this brand. The results are very visual and make an idea of which may improve performance or comfort with this type of clothing.
In addition to the commented Shock Absorber, made with active fibres which are shortened to notice the movement of the chest, also has come out recently the Nike Revolutionary Support Bra, made with woven dry fit and seamless. Already for taste colors, the important thing is to know how to choose the fabric that best suits your characteristics, reduce movement and increase the comfort. Here you have a video that you see the difference between running with a good sports bra and a normal bra: