For women whose search for a comfortable sports bra has been long and fruitless, scientists believe they are close to an answer.
Research has identified how the different parameters of breast movement -- distance, velocity and acceleration -- are linked to discomfort during exercise, The (London) Times reported Monday.
Joanna Scurr, director of the Breast Health Unit at the University of Portsmouth, who led the project, said, "Until now bras have been designed in a completely ad hoc way. It's amazing that the science hasn't been done before."
The study, published in The Journal of Sports Sciences, monitored the breast movements of 15 female volunteers with a D-cup bra size as they ran on a treadmill. Using infrared cameras, which monitored sensors attached to their chests, movement was tracked in 3D while the women ran without a bra, with an ordinary bra and with a sports bra. The women then rated their discomfort on a 1-5 scale.
"Up to 72 percent of women experience pain or discomfort either during or after exercise," said Scurr. "Whether for elite athletes or once-a-week joggers, this can have a negative effect on your performance and can also deter women from taking part in physical activity."
Previously it was assumed that the distance moved by the breasts would be the most important factor, but the study showed that the speed of breast movement accounted for 56 percent of pain during running. The distance the breast moved accounted for 43 percent and acceleration 37 percent.
Scurr's team also found that it was only the side-to-side motion of the breasts that hindered performance, suggesting that horizontal support was an important factor. The Portsmouth group is now working with manufacturers to draw up new criteria for the ideal sports bra.
A second study of 100 women showed that breast pain in those who exercised once a week was not linked to breast size and was as just as likely for women with an A-cup as an F-cup.
Amanda Brasher, chief womenswear buyer for the retailer Sweatshop, predicted that sportswear companies would be quick to adopt new scientific criteria to gain a competitive advantage. "For years, sports companies have spent a lot of money developing technology for trainers and smart fabrics. It's only in the last five years that the focus for women's sportswear has shifted to bras," she said. "A good sports bra can make a huge difference to how much you enjoy your sport."
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