The Biomechanics of Women's Breast Movement During Running

Joanna Scurr, a biomechanics professor at the University of Portsmouth in England has been studying the biomechanics of breast movement during running, and the effectiveness of various bra technology in minimizing the movement.

(Professor Scurr measures breast movement with the use of eight motion detectors;
photo courtesy of the University of Portsmouth)

Some interesting facts from her study:

1) During walking exercise, the women's breasts moved relatively the same amount in all directions. But when participants sped up to a jog or run, their breasts moved proportionally more in some directions than others: More than 50 percent of the total movement was in the up-down direction, 22 percent side-to-side and 27 percent in-and-out.

2) The overall pattern of the movement resembled a figure-8.

3) An estimated 50 percent of women experience breast pain during exercise. Yikes!

4) Typical bras are made to reduce up and down movement. So-called "encapsulation" bras are a bit better than "compression" bras at reducing movement in other directions - in A-cup women, wearing a sports bra reduced overall breast movement by 53 percent, compared with a 55-percent reduction for G-cup women.

Holy cow! Could it possibly be true that there is that much movement? If so, that's gotta hurt. Particularly for ultra-distance athletes. Before I caught myself staring at all women on my next run to "confirm the facts", I thought I would look for some online video. A quick video of Pamela Anderson is "enlightening" (women, please excuse my dudeness - really, it's for science!):



Professor Scurr is now working with apparel manufacturers to put her study into new products, so perhaps more advanced help is on the way. In the meantime, Coach Wendy at Trifuel has an informative article on choosing a jog bra here.