With the Dublin Marathon approaching, for those taking to this year’s start line much of the hard work has already been done. The mileage has been upped, the shoes trialed, the carbs loaded. Now all that remains is to run the damn thing.
This year, 36 per cent of runners entered in the Dublin Marathon are women, the majority of whom will have to contend with a piece of kit that’s often overlooked: the sports bra.
“We’ve done a lot of research into this over the past 10 years,” says senior research associate at the University of Portsmouth, Nichola Renwick, “and we’ve seen that it’s not just a case of breast pain that’s experienced in wearing a poor-performing sports bra, it does actually affect running performance as well.”
Wearing an ill-fitting sports bra causes a woman to reduce her stride length by 4cm. Over the course of a marathon that adds up to about a mile.
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“The version of you with the better fitting and better supporting sports bra is going to be finishing a mile ahead of you,” Renwick explains.
And the downsides of wearing the wrong sports bra don’t stop there. “We’ve also seen that it can make the rest of your body work harder. Your upper body muscles, they’re in a bit more tension, so they’re working harder throughout the activity almost to guard that excessive breast movement from the bra not fitting properly and not providing enough support.
“That will then make you tire quicker as well, so you’re not going to be able to exert as much energy as you’d like to focus on your performance. That can also impact your breathing, and we’ve seen that people breathe less frequently when they’re not in the correct kind of supporting bra.”
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Research has also raised the question of the impact sports bras may have in leg injury risk.
“We’ve done research that has seen that the ground reaction forces [how hard your foot hits the ground while running] can change depending on the support level of bras, so wearing the correct support can reduce those ground reaction forces which theoretically means that it’s reducing the amount of force and harm coming at the body during activity,” says Renwick, adding the caveat that “a lot more research that needs to be done” in the area.
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But it’s one thing to know what makes a good sports bra and another to make sure they’re available for running enthusiasts and novices alike.
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“They want to improve,” Renwick says of the sports manufacturers who work with University of Portsmouth to test the efficacy of their sports bras. “The sports bra industry is growing massively so they want to build and drive this market.
“I think now, the sports bra is being taken more seriously within the industry as a piece of kit and having a function, not just being a fashion piece.
“That’s really driving different approaches to design, and we work really closely with a lot of [brands] who are doing some interesting things that are really trying to crack open what a sports bra is doing and how can we change it and how can we improve it.”
Tips for picking the right sports bra
What to look for:
- “Encapsulated” or “combination/hybrid” styles
- High neckline (each centimetre reduced breast bounce by 1 per cent)
- Adjustable straps (shoulder and back)
* Strap configuration (racer, T-bar, criss-cross, etc) is personal preference
Signs of a poorly-fitting sports bra:
- Rubbing
- Chaffing
- Digging
- If you’re aware of your breasts (“If you’re wearing the right bra, you’re not even aware that you have breasts,” says Renwick)
Normal bra-fitting advice still applies:
- Band isn’t riding up more that 5cm at the back
- Straps are not digging in, but also can’t be pulled more than 5cm up from the shoulder
- All breast tissue is sitting in the cup – no bulging or gapping
- With encapsulating styles, centre panel between the cups should be flush to the chest bone
