Young Teen College Girl Without Brassiere

A number of reports state the 80-85% of women are wearing the wrong bra size. A correctly fitted bra is determined by accurately calculating the chest size (or band size) and breast volume (the cup size). The band size can be adjusted slightly using the two or three alternate sets of fastening hooks and eyes in the clasp. The bra straps (over the shoulders) can usually also be adjusted slightly.
• Mechanical design
Bra designers liken designing a bra to building a bridge, because similar forces are at work. Just as a bridge is affected vertically by gravity and horizontally by earth movement and wind, forces affecting a bra's design include gravity and sometimes tangential forces created when a woman runs or turns her body. "In many respects, the challenge of enclosing and supporting a semi-solid mass of variable volume and shape, plus its adjacent mirror image—together they equal the female bosom—involves a design effort comparable to that of building a bridge or a cantilevered skyscraper."
Commenting about brassiere design, British Chiropractic Association representative Tim Hutchful said, "Bras are like suspension bridges. You need a well-engineered bra so your shoulders don't end up doing all the work. Bras that don't fit will affect the shoulders and chest, and will almost certainly cause back pain as you get older."