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Why a too-tight sports bra may affect your breathing and energy

A new study suggests that for fast runners, wearing a sports bra that has a tight underband may impair breathing and negatively impact how efficiently they can run

March 13, 2024 at 1:21 p.m. EDT
A too-tight bra can affect your breathing and impede running performance, research suggests. (iStock)
6 min

When shopping for a sports bra, many athletes believe that the tighter and more snug, the better. But new research suggests a too-tight bra can affect your breathing and impede running performance.

The study, which was funded by athletic apparel brand Lululemon and conducted by researchers at the University of British Columbia, tracked the breathing and lung function of nine elite runners as they ran on a treadmill wearing a custom sports bra with a lower band that could be adjusted to tight, loose or a standard size the runner chose.