Playtex公司的阿瓦罗斯-丹斯内说，文胸有提升和支撑的作用，需要平均分配重量。设计文胸就是挑战重力作用。

Good bras can have more than two dozen working parts. Seams support stress points and create shape. Rigid stays prevent the fabric under the arm from crumpling. Stretch lace at the top of the cup looks decorative, but it has a function as well: It ensures a smooth fit even when a woman's breasts aren't exactly the same size. The straps don't actually support the weight in a bra, but they do need to be firmly anchored into the band to distribute tension.

一副好的文胸有二十多个着力点。接缝线起到支撑应力点和塑形的作用。撑条保证腋下的部位不会起皱。罩杯顶部的弹力花边看似只是一种点缀，实则也是有其实际功用的：当胸部的尺寸与文胸大小不是完全一致时，有了这个花边，看起来也会比较合身。肩带不会直接承受胸部的重量，不过必须跟下扒紧密相连，以分散下扒对身体的压力。