Not all sports bras are created equal. To ensure maximum support while you work up a sweat, you need a bra worth its stuff. Why, you may wonder, are sports bras so important? Over time, the ligaments that attach the breasts to the body stretch and can cause sagging. A sports bra helps protect against that stretching sensation during your workout, holding your breasts close to the body even when you're pounding the treadmill. So whether you're an A cup or D cup, sports bras are a must.

Since women come in many shapes and sizes and athletic endeavors in many varieties, you'll have to find a bra that works well for your particular shape and sport. While you may burn 600 calories in that hot yoga class every Tuesday and Thursday at the crack of dawn, the amount of support you'll need isn't the same as when you're jetting to an hour-long spin class or busting out a 2-mile run during your lunch break.

The Best Bra For: Running (Extreme Impact)

To find the best bra for running, look no further than running superstore roadrunner.com. Ranked as one of the most popular on the running retailer's site, the Women's Moving Comfort Fiona Bra has armholes and contours designed specifically to cut down on chafing as your arms pump back and forth when you're out pounding the pavement. The bra has molded cups and adjustable straps. The best part is even the bustier runners out there will be comfortable in this bra - Prevention Magazine ranked it as the "Best Bra for Ds and up." $43.99