Don’t underestimate the power of a sports bra

Health in a Heartbeat

For women who take running seriously, your sports bra can be friend or foe.

A new study suggests that wearing a sports bra with an underband that is too snug can impair breathing and cause athletes to run less efficiently.

The study monitored the breathing and lung function of nine elite runners as they wore a sports bra with an underband that could be adjusted tightly, loosely or at a tension chosen by the runner. Th athletic apparel brand Lululemon funded reseach by the University of British Columbia.

The women ran with a catheter in their esophagus to monitor their breathing.

Study participants’ rib sizes measured from 30 to 34 inches and they wore a B or C cup.

As they ran wearing tight underbands, they took more frequent, shallow breaths. Once the bands were loosened, the runners needed less oxygen and ran more efficiently.

When selecting a sports bra, women — especially those with a larger bust size — often opt for a tighter bra to prevent chafing and movement.

Going from a tighter underband to a looser one gave the runners, on average, a 1.3% improvement in running economy. Over a three-hour marathon, a 2% improvement would shave three minutes.

While earlier research found that women with larger breasts enjoy better running economy when wearing high-support sports bras, those studies didn’t focus on underband tightness.

The takeaway message for those fleet of foot is that sports bras matter. Support is important, but don’t overlook how it affects your breathing.

And if sports bra manufacturers can make one that isn’t impossible to peel off after a sweaty workout, female weekend warriors will celebrate.