Running, yoga, biking -- all these activities can require varying degrees of bra support. And for women with larger breasts or unusual bra sizes, it can be difficult to find a bra that does the job.

On November 16, fitness website Fit Bottom Girls published a sports bra guide that aims to get the bounce under control.The first step: know your bra size. To help you along, visit the bra school at Linda "The Bra Lady" Becker's website (see below for link), which offers a bra fitting calculator. For European sizes, convert from inches to centimeters, but the cup size remains the same.

"One of the easiest and quickest ways to determine if a bra will be supportive is to check the straps to see how much stretch they have," said Katie Vogt-Saladucha, a bra fit model for the past 23 years who has worked with major US brands Victoria's Secret, Gap Body, Wacoal, Bali, and Maidenform, in a interview with Fit Bottom Girls. "The more stretch, the more bounce the garment will have." She adds: "Look for straps that are reinforced or padded -- especially for bigger busts -- and have little to no stretch." For high-impact bras, look for little to no stretch in cups and minimal stretch in the band of the bra.