Bras for Athletic Backs:
A Back-First Fit Guide for Broad Shoulders and Lats.
Why fit starts at the back
Traditionally, bras are designed cup-first. But what happens when your upper back is wider than your rib cage, and your torso is closer to a triangle than a rectangle?
If you swim, climb, lift, dance, do gymnastics, or were simply born with broader shoulders, chances are your upper back is wide while your rib cage and waist stay narrow. Technically, you have two sizes in one body: your upper back measures one size, and your rib cage measures another.
The problem: Bra size charts ask for your underbust and bust. They don't ask for the measurement at your underarms, where your lats are. They assume your back runs straight down like a rectangle. Yours tapers like a triangle, so the band cuts in and causes backspill.
That's why we start every design at the back. Below, we'll walk through it piece by piece and show what we do differently.
Just need your size? Jump to the back-first size chart.
The anatomy of an athletic back
An athletic back changes three places a bra has to fit: your traps, lats, and rib cage. Here's what you feel in each, and why it happens.
Lats: when the band cuts in and causes backspill
If the band pinches into the sides of your back or you get backspill, your lats need more room than the band gives them. Lats flare out at the sides of your upper back, wider than the rib cage below them. A standard side panel runs straight across, so it cuts into muscle instead of following its curve.
The Daylilie Fix: a V-shaped side band that scoops to make room for lat flare, so the band follows the muscle instead of cutting across it.
Traps: when shoulder straps keep slipping off
If your straps slide off no matter how tight you pull them, your traps are likely the reason. Developed traps create a downward slope from your neck to your shoulder, and a strap sitting on that slope slides right off. Tightening it doesn’t help, it just adds pressure at the shoulder.
The Daylilie Fix: We position the straps to stay put on both sloped and flatter shoulders, tested on fitters with and without developed traps.
Rib cage: when you are stuck between two band sizes
Size up so the band fits your lats, and it’s too loose around your rib cage, so it rides up. Size it to your rib cage, and it’s too tight across your lats. That’s the two-sizes-in-one-body problem, and it’s a design problem, not a sizing one.
See how our feature work together:
How to measure an athletic back
Use a soft tape, stand relaxed, and breathe out normally.
Underbust
Exhale naturally and measure around your ribcage, just below your bust. The tape should hug you snugly and comfortable, but not tight.
Bust
Breathe normally and measure around the fullest part of your chest
Underarms
Let your arms hang naturally and measure around your body at armpit level