Sports Bra Sizing & Support Guide

Convert your everyday bra size into reliable sports support by pairing impact categories with the right structure, straps, and fit tests.

Impact levels at a glance

Low impact

Yoga • Barre • Walking • Recovery days

Focus on breathable fabrics with gentle compression or lightly structured cups. Ensure the band stays supportive without restricting ribcage expansion.

Medium impact

Strength circuits • Cycling • Hiking • Dance

Hybrid bras that combine encapsulated cups with moderate compression keep tissue lifted while permitting dynamic movement.

High impact

Running • HIIT • Court sports • Jump training

Prioritize encapsulation for each breast plus a compressive overlay. A firmer band and adjustable straps reduce vertical and lateral bounce.

Band & cup strategy

Start with the calculator result, then adjust band tension depending on workout intensity.

  • High impact or larger bust? Test the tighter sister band (down one band, up one cup) for extra anchoring.
  • Low impact or rest days? The looser sister band can keep you comfortable while maintaining coverage.
  • Document which brands run firm or relaxed—adjust your starting point accordingly before reordering.

Support style breakdown

Classic straps

Easy to adjust and ideal for medium impact. Ensure sliders stay high on the back to prevent slippage.

Racerback / cross-back

Centers support and minimizes bounce during running or plyometrics. Look for breathable mesh to offset the extra coverage.

Convertible straps

Best for multi-sport wardrobes. Switch between classic and racerback depending on the session.

Post-fit movement tests

After wearing the sports bra for a few minutes, run these diagnostics to confirm performance.

  • Jump in place for 10 reps—observe breast movement and ensure the band stays anchored.
  • Reach overhead and twist side to side; the lower band should not roll or shift.
  • Check the center front for gaping or air pockets. Encapsulation cups should sit flush.
  • After perspiring lightly, re-check comfort. Moisture-wicking fabrics should stay smooth, not abrasive.

Sport-specific playbooks

Frequently asked questions

Do I need a different size for sports bras than everyday bras?

Use the calculator result as your baseline, then test one tighter sister band for high-impact sessions. Fit should feel firmer but still allow full breaths.

How often should I replace sports bras?

Every 6–12 months depending on workout frequency. Loss of rebound in the band or straps is a sign to replace.

Can compression-only bras support fuller busts?

Compression alone may be uncomfortable for fuller busts during high impact. Opt for encapsulation or hybrid designs to distribute weight evenly.

Ready to convert your measurements?

Start with the calculator, then open the Sports Bra Advisor tab to tailor support to each workout.