Athleisure · From the Tryoom app
How to Find a Sports Bra That Actually Fits
About 80% of women wear the wrong sports bra size. The fit problems aren't subtle: back pain, bouncing, chafing, straps digging in.

How to Find a Sports Bra That Actually Fits
About 80% of women wear the wrong sports bra size. The fit problems aren't subtle: back pain, bouncing, chafing, straps digging in. The diagnostic comes down to three checks and one rule about how the support actually distributes.
The 80/20 rule
The underband does 80% of the support. The straps do 20%. If you've been tightening straps to compensate, the band is too big.
Three checks
- Underband: snug enough that two fingers fit underneath, no more. The band should sit horizontally around your ribcage, not ride up at the back.
- Cups: no gapping at the top, no spillage on the sides. If there's a gap, the cup is too big. If it's spilling, too small.
- Straps: shouldn't dig in or fall off. You should be able to slide one finger under each strap with mild resistance.
Match the impact level
- Low impact (yoga, walking, Pilates): light compression, thin straps fine.
- Medium impact (cycling, hiking, lifting): wider band, encapsulated cups.
- High impact (running, HIIT, sports): wide racerback or cross-back straps, structured cups, possibly underwire.
The replace clock
A sports bra worn 2-3 times a week loses elasticity in 6-12 months. If the band rides up or feels loose where it used to feel snug, replace it. Old elastic doesn't return to support, no matter how many times it's washed.
Care
- Cold wash, mesh bag, hang to dry.
- Never tumble dry. Heat destroys the elastic faster than wear does.
- Rotate at least three sports bras to give the elastic 48 hours to recover between wears.