If you're choosing a sports bra for a high-impact activity like running, you probably want something that's going to provide you with plenty of support, but new research suggests that if you go too tight, your performance could actually decline.
The study, which was conducted by researchers at the University of British Columbia and funded by Lululemon, took nine "highly trained" female runners with normal pulmonary function and had each one undergo maximal and submaximal running while wearing sports bras that were loose, tight and self-selected fit.
The researchers observed that sports bras with tighter bands may compromise respiratory function and whole-body metabolic rate. When looser, they observed that the runners took deeper, less frequent breaths and enjoyed better running economy. They concluded that loosening the pressure presented by the band of your sports bra may essentially decrease the work of breathing.
This isn't the first time that scientific studies have noted a connection between sports bras and performance – in 2023 we reported on a correlation between a more supportive bra and improved knee stiffness, which improves running efficiency. The key is to find a bra that is supportive around the cups without being overly restrictive in the band. Learn more in our article on how to fit a sports bra for running.
