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The making of On’s sports bras

They say it takes a village to raise a sports bra. Well. Something like that. Here’s how three designers, one lab, many sports scientists, and countless athletes helped shape the new On sports bras.


We were sick of sweaty underboobs, too much cleavage, not enough support, nipple chafing, and getting stuck in our sports bras.


The dream outcome? Bras we don’t want to hurl on the ground when we’ve finished working out. Bras that support without suffocating. That do what they’re supposed to, so we can ignore our bras completely, and focus on what really matters.


As we know all too well, many sports bras that have come before have tried and failed. Time to (ahem) bust out the A-Team.


The support squad



The team behind On’s sports bras are Apparel Development Lead Fiona King, Apparel Designer Stefanie Herbstrith, Performance Running and Outdoor Lead Annaleigh Hockaday, and Sport Science Lead, Dina Weisheit.       


“My bra is as important as what I’m wearing on my feet, almost to the point that I’d rather run barefoot than run without a bra,” says Annaleigh.


But despite sports bras being so high on their priorities lists – the whole team have had difficulty in finding “the one”.



“It’s a bit of a love/hate relationship with sports bras,” says Dina. “I love them and need them for any workout, but also finding one that fits, gives the right level of support and doesn’t rub against my skin is super tough.”


“Because I have quite a big chest I’ve always struggled with sports bras,” explains Fiona. “I never even entertained the idea of one until my late teens because it just wasn’t an option.”


The other designers on the team have all struggled to find their perfect sports bra for different reasons. But, that’s been a good thing, Fiona says. “We’ve all been able to come at it from a fresh place, without constantly comparing what we’re creating to our favorite sports bras – because none of us had one.”



Creating the dream bras


These sports bras have been in the works for four years. Seriously.


“It’s been a long process trying to figure out what a good sports bra needs to do, and respectively, what it needs not to do. And how to make that possible,” says Dina. “The first sports science test we did dates back to the beginning of 2021, and since then we have tested five versions of the sports bras to get to this point.”


So, after a lot of lab testing (which we’ll get on to later), this is what the new On sports bras have to offer.


360 support

The support offered by the Performance Bra and the Active Bra takes the form of a single slightly padded piece that’s designed to support each breast from every angle. The single piece construction also means you don’t need to worry about any interior seams causing irritation or chafing.


So, whether you’re treadmill training, sprinting around a tennis court, or tackling a burpee-themed HIIT workout, we’ve got you covered. Simply choose the Performance Bra for higher impact activities like running, or the Active Bra for lower impact sports like yoga and spin.




Is there anything more annoying than feeling pools of sweat in your bra mid-run? Probably. But a sweat-drenched chest is one distraction you don't need.


In both bras, we’ve used technical fabric throughout to wick sweat away from your skin as fast as possible. And at the back we’ve added a full mesh panel to let the heat out and help it dry in super-quick time.



Stepped-up straps

One of the main pain points of sports bras is getting them on, and off again. We get it.


The racerback on both the On sports bras is ergonomically designed to be as easy as possible to get on and off, even when you’re sweaty. Made of premium elastic, the straps are created to stretch to make getting in and out easy, as well as provide support that moves with you.


You might also notice that the straps are a bit wider than other sports bras. By making them wider over the top of the shoulder, the straps even out the distribution of that pressure – meaning you won’t experience painful straps digging in while you’re running. They provide great support for vertical breast movement, too.



Testing, testing, testing.


To make sure the bras were performing at the highest possible level, we worked with Progressive Sports Technologies based at Loughborough University to do some thorough testing in a controlled environment. We used the testing to take a deep dive into how breasts move when they’re in motion (it’s about way more than just bounce control), as well to measure how the On bras performed against some of the other most popular bras on the market.


“The testing process is so important as it is the only way to understand if our product actually does what we want it to do,” explains Dina. “We combined fit and wear testing with biomechanic testing to understand the objective performance of the product and to correlate it with the perception of the runner, to understand not only how the bra is working but what the wearer is feeling.”


The team at Progressive Sports Technologies compared the Active Bra and the Performance Bra to some of the top bras on the market. It also measured breast movement in all directions, focusing on peak to peak (up and down) movement. This is the most important one, as without proper support, it can result in damage to the breast tissue (ouch).



Top-notch results


The results? Well, we were pretty happy. Both the Active and the Performance Bra not only performed the best from a data perspective, but were also perceived to be performing the best. So the wearers also felt like the On bras were the most supportive and the most comfortable out of all the ones they tested.


This is significant, as even though a bra might technically be holding the breasts in place — if it’s uncomfortable, it’s going to stay in the drawer.


Here are the highlights:

The Active Bra was ranked as the most comfortable and the least restrictive overall, with the Performance Bra ranking as the most comfortable of the high support bras.


The Performance Bra was rated as the most supportive against all competitors.


This is also supported by science: the Performance Bra had significantly lower horizontal breast displacement (less nipple movement) than any other bra in the testing. And, as for up and down movement, it scored equally to the most supportive bra.


These results contradict what is generally believed to be true about sports bras, that in order for a high impact sports bra to work, it needs to be compressive and restrictive. Enter, the Performance Bra - with both a high support ranking, and a high comfort ranking.



What the testers had to say


As well as lab testing, we also wanted to check that the bras worked out there in the wild. We needed to make sure that the bras can stand up to daily use, survive the washing machine with aplomb, and handle anything else that might come their way.


In each round of testing, each bra gets a minimum of 350km of wear over a mix of activities like yoga, spinning, running, Pilates and even just everyday use. Because we all know that a comfortable bra should never be limited to just one activity.


So we recruited some On athletes to wear the bras, and send us feedback and ideas on how we could improve them.


For example, one of our testers pointed out that in one of the original prototypes, the clasp was annoying when she was doing mat work or stretching out after a run. So, we removed it, making a supportive, clasp-free and comfortable upgrade. And that’s just one example of how our athletes were invaluable in the making of the On sports bras.


Here’s a few favorite quotes from our testers:


Active Bra:

"I could sleep in this… It‘s so soft, it doesn‘t feel like you‘re wearing a sports bra."

“Impressed by the premium look, it looks super sleek and nice. Putting it on for the first time also felt really good (wasn’t too hard to get on), it fits very nicely, and felt good during my low-intensity class.”


Performance Bra:

"I really like the feeling of the bra on my body, no matter if it‘s sweaty… or not. The material doesn‘t feel wet or cold and it dries super quickly."

"I‘m super happy with the comfort of the bra. It feels compact but doesn‘t constrict anywhere. The seams are very soft and don‘t interfere with any movement."


The Performance Bra
High impact, high coverage and high comfort.
Explore now
The Active Bra
Comfortable, strappy and distraction free.
Explore now

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