I just received this from Exercise, Etc. and thought it had good information for finding a good workout bra. Ow, breast tissue can move as much as 8" when running, in all directions.
Exercise and Breast Pain in Women
Now you may think that the topic of breast pain in women who exercise is unusual, but scientists in England have found that it can be profound enough that it affects training and workouts. It makes sense that the larger the breast, the more complications. Of course, a well-fitting sports bra has been shown to help in as many as 85% of women. However, a large number of women, including the 1300 surveyed who ran the London Marathon, are not wearing the right bra.
Researchers found that the breast tissue can move as much as 8 inches in space when running, not just up and down, but side-to-side, and forward/backward. This can cause enough pain that 25% of these women either reduced their intensity or skipped exercise all together.
The Research Group in Breast Health suggests following these 5 simple steps to a correct bra fit:
1) BAND - The band should fit firmly around the chest. It should not slide around as you move, but it should not be too tight to be uncomfortable, affect breathing or make flesh bulge over the band. The band should be level all the way around the chest.
2) CUP - The breasts should be enclosed within the cups, with no bulging or gaping at the top or sides. If the cup material is puckering then the cup size is probably too big.
3) UNDERWIRE - The underwire should follow the natural crease of the breasts and not rest on any breast tissue (in the center, underneath the bra or under the arms). If the underwire is resting too far down the ribcage (i.e. where the ribcage gets slightly narrower) the band size is probably too small.
4) FRONT - The front of the bra (the lower edge under the breasts and between the cups if a separate piece exists) should sit flat against the body and not gape away from the chest. If the front of the bra is lifting away the cup size may need to be increased.
5) STRAPS - The shoulder straps should be adjusted to comfortably provide breast support without being too tight (i.e. digging into the skin). The main support for the breast should come from a firm band, not tight shoulder straps.
Brown, N. et al, "The Experience of Breast Pain (mastalgia) in Female Runners of the 2012 London Marathon and its Effect on Exercise Behaviour" Br J Sports Med bjsports-2013-092175Published Online First: 19 April 2013 doi:10.1136/bjsports-2013-092175