From humble beginnings — the first modern sports bra was fashioned from two jockstraps sewn together — the sports brassiere has emerged as a high-tech apparel powerhouse.
A triumph of engineering over gravity, these slight pieces of fabric are now researched and tweaked to the minutest detail.
Some are even tested in biomechanical labs with cameras rolling, reflective tape recording every bounce of the breast, every twist of the nipple.
Just one garment can include eight types of fabrics, with varying amounts of support, sweat-wicking properties and ventilation levels.
As a category, they’re made with ever-more-smooth microfibers to reduce friction.
Even the straps are specially engineered, some with gel inside for added cushioning.
These advances have been fueled by the growing expectations — and changing needs — of women and by the indefatigable efforts of researchers who have made bounce analysis and nipple-tracking a fine art.
One of those scientists, LaJean Lawson, has been conducting sports bra research at Oregon State University’s biomechanics lab for nearly 20 years.
Today she is an adjunct professor in exercise and sports science and works with Champion Athleticwear to test and improve sports bra designs.
To test a bra, Lawson relies on a shifting group of volunteers with varying breast sizes.
The women jog on a treadmill at a 6-mph pace, while six cameras set up around them feed data into a computer.
Lawson is able to track the motion of the breast in the bra to the smallest detail.
At the end of each trial, Lawson will have simulated figures of the subject’s entire body in motion and of the breasts, moving up and down in space.
She can track in slow motion every twist and turn of the breasts, which tend to move in a figure-eight pattern that reflects the arm swing and shoulder rotation during running.
"We can tell you how fast the nipple is going as it changes direction," she says.
In fact, she says, some of the data are kind of scary.
"Think of when you play crack the whip," she says.
"The skin and much of the underlying tissue in the breast is somewhat elastic, so when you have a breast traveling downward at a pretty good rate of speed, and then you change direction as your body hits the ground and begins to rise up again, you can get some pretty drastic acceleration as the breast speeds up to try to catch up with the rest of the body.
The point of the sports bra is just to slow all that down."
The average 36C breast is estimated to weigh about 10 ounces.
Researchers calculate that a breast of this size, with minimal support, running at about 5.6 mph, will bounce as much as 4.7 inches up and down, relative to trunk movement.
A good sports bra can decrease this by about one half or more.
Today, Lawson says, breasts are moving somewhat differently in the bras that she’s used as controls over the years.
This is due, she suspects, to a higher ratio of fat-to-glandular tissue in the breast.
In the last 10 years, breasts have increased from an average bra size of 34B to 36C or 38C.
To fully understand the breast, one must start with the fine strands of connective tissue, called Cooper’s ligaments, that separate its lobules.
"The bra can’t control the inherent elasticity of the ligaments," he says.
Whether bounce causes sag may be debatable, but comfort isn’t.
"We rode the growing wave of women participating in college sports," recalls Miller, linking the emergence of sports bras with the passage in 1972 of Title IX.
That landmark legislation prohibited gender discrimination in schools receiving federal assistance, with much of the impact felt in athletics.
"Over the years the sports bra has changed how we look at our bodies," says Miller, "and it acknowledges that women of all sizes are entitled to exercise and be fit.
"Theoretically, a loose, stretchy bra with a large breast in it can actually propel things a little faster," says Lawson, "if extreme stretching and recovering of the fabric is occurring.
- Source: Los Angeles Times, via Inside Bay Area, May 17, 2006
