Research shows that sports bras that are too tight can affect women's breathing, making them shallower and taking several extra breaths per minute. Additionally, loosening the band reduced the runners' oxygen consumption at a given speed. This means your running economy, which is the amount of oxygen consumed at a given speed, has improved.
Experts recommend that runners wear sports bras that provide adequate support but are not too tight around the ribcage.
“People ask, 'What kind of sports bra should I wear?' I say, 'Wear one that fits properly,'” said the study's lead author, now a Ph.D. at the Mayo Clinic in Minnesota. said researcher Sharaya Kipp. “That's probably the biggest help.”
How tight bras affect breathing and running efficiency
Kip, a 2012 Olympian steeplechase, also participated in the study as one of nine subjects. Runners wore compression bras designed for women, and bra sizes ranged from 30 to 34, representing the band size around the rib cage, and B or C cups.
The authors hypothesized that when a bra tightens around the ribcage, respiratory or lung function may be impaired. “Decreased lung function makes it difficult to breathe, which is especially important during exercise and daily physical activity,” Kipp said.
To measure it, the researchers inserted a catheter that went through the nasal cavity and into the esophagus.
“It was pretty invasive,” Kipp said. “This is the most difficult experimental protocol I've ever had someone do.”
Runners completed various treadmill tests to measure running economy, adjusting the tightness of their sports bra each time. An improved version of Lululemon's Energy Sports Bra was customized to allow participants to adjust the tightness of the underband around their ribcage without having to take off their bra.
Overall, researchers found that loosening the underband allowed runners to breathe deeper and less frequently and run more efficiently. All of these can affect your running performance and comfort.
Dalini Bammer, an assistant professor of internal medicine at The Ohio State University, called this “a very mechanistically powerful study.”
“No one has looked at underband tightening separately from overall chest support, and no one has worked on breathing with a sports bra, because that's a really difficult measurement,” says Respiratory Physiology. said Bammer, whose research focuses on “So this is a really nice, kind of novelty in this study, and that's what makes it special.”
How the findings apply to runners
The study found that changing the underband from tight to loose improved running economy by an average of 1.3%.While doing so It may not seem like much, but it's enough to affect your running performance. Kipp said his 2% change in running economy translates into an improvement of 3 minutes for him to a 3-hour marathon runner.
Kim Conley, an Olympic distance runner who was not involved in the study, said she had never thought much about the tightness of sports bras or breathing, but Kipp's research changed her mind.
“This is important for elite runners, especially as qualifying standards become increasingly strict,” Conley said. “Everyone wants a profit of even 1%. I think this is important, so I'd like to think about it from now on.”
Laura Hernandez, 25, of Boston, is a trail runner who is training for her first road marathon this year. She said she runs at a pace of about 8 to 9 minutes per mile, and she's “shocked” that sports bras don't come up more often in her conversations about running gear. “She's as essential as sneakers,” she said.
Because she is concerned about chafing, she often ends up wearing tight sports bras. “But now that I've seen this study, I'm thinking about where the line is between not being too loose to rub, but not too tight to restrict breathing,” she said. “I think I only saw one side of that line.”
Also, the feeling of wearing a sports bra differs when you are at rest and when you are exercising. Kipp pointed out that most women choose sports bras based on the former. She recommends trying on sports bras just like running shoes. “Increase ventilation,” Kip said. “Take a deep breath in the locker room.”
Don't forget to support us
This study focused on tightening the band around the ribcage rather than supporting the entire breast. Other studies on women with different bust sizes found better breast support Supports runners, reduces oxygen consumption and improves running economy.
Douglas Powell, director of the Breast Biomechanics Research Center at the University of Memphis, said people with larger breasts may benefit more from a supportive sports bra. He is a co-author of a 2022 study that found increasing support in a sports bra improves running economy.
In that study, 14 participants ran on a treadmill in various sports bra conditions. Researchers recruited recreational runners with bust sizes ranging from B to DD cups.
They found that when participants ran wearing a supportive sports bra, their running economy improved by about 7% on average.
“We believe that reducing chest movement reduces the effects of sway and increases running efficiency, which contributes to improved economy,” he said.
Powell called the new study's data “interesting” and said it doesn't contradict the conclusions of his own study because it focuses on different aspects of sports bra design. “I would like to understand that we need to start considering narrowness of bandwidth as a factor to look at,” he said.
Haley Fong, lead author of the 2022 study and a doctoral student studying sports bra biomechanics at the University of Memphis, said the participants in the study were very different and that further research in the field. He said he welcomed the research.
“I think the biggest thing to take away from all these papers and all the research that we're doing is that support is important and the sports bra that you're wearing is important,” she says. I did.
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