I wore sports bras instead of proper underwire and moulded-cup bras for most of my teens. My flatter-than-a-’90s-blowout chest had suddenly become a very full C cup, and since I played soccer nearly every day, it was easier to compress and bind my breasts into a snug sports bra rather than fuss with all those straps and clasps. And, aesthetically, I didn’t hate the uniboob look.

Even though I have since graduated to grown-up bras outside the gym and barre class, I consider myself a sports-bra connoisseur. So when Lululemon invited me to try its new Enlite sports bra, I (quite literally) leaped at the chance. Which is how I found myself running on a treadmill in the brand’s Vancouver HQ wearing the bra, with several tiny reflective sensors attached to my chest and eight motion-capture cameras recording my – or, rather, their – every movement. (More on that in a sec.)

Lululemon has been slaying in the sports-bra category since its launch nearly 20 years ago (thanks especially to its user-friendly support-ranking system). After soliciting customer feedback, however, the Canadian brand realized that women often sacrifice comfort for performance or vice versa. I can relate; I’d often squished myself into a too-tight bra with the hope of getting extra support. I figured that the less the breasts shift during exercise, the better, right? Not necessarily.

 

 

Here’s where those motion-capture cameras come in. As I jogged, they recorded the path of the sensors. This info, when uploaded onto software, showed in real time how (and where) my breasts moved. Through this biomechanical testing – which had been done on 100 women prior to my own interactive experience – the team uncovered something surprising: Not all bouncing is painful. In fact, breasts move in a 3-D figure-eight pattern. Research is mixed, but experts believe that it’s mostly the up-and-down and, to a lesser extent, forward-to-back parts of this motion that cause discomfort, not so much the side-to-side shifting, says Michelle Norris, a sports and exercise science researcher at the University of Portsmouth, in England. (If uncontrolled, that hurt is real: A 2013 study published in the British Medical Journal found that 32 percent of female marathon runners experience breast pain. Worse, other studies have shown that women will avoid exercise because of their chests.)

Then, the eureka moment: Why not restrict only the movement that causes discomfort? “We’re shifting from the idea of making the movement smaller to really embracing it,” says Chantelle Murnaghan, innovation manager of engineer sensation for the brand’s research lab, Whitespace. To that end, the Enlite is an encapsulation style, which means that the breasts never touch and aren’t compressed. (Compression-style bras squish the breasts to the chest – remember the uniboob.) Encapsulation bras are thought to be especially beneficial for women with a larger bust, says Norris. “Each breast is encased individually in its own cup, effectively halving the mass that a compression sports bra has to deal with.” Think the same support with less “I can’t breathe” feeling and the added benefit of a curved shape – underneath a T-shirt, the Enlite creates the same curved definition as a T-shirt bra. (The material is also double layered in the cups.) And while, at $98, this is the most expensive bra the brand sells, the design has over two years of research behind it.

 

 

Material was thoughtfully considered; the Enlite is made of Ultralu, a sweat-wicking nylon-Lycra blend that stretches easily but springs back into its original form. This ensures optimal tension in the underband, the part that encircles the ribs, which is the main source of breast support. This material means that the company can forgo fussy adjustable straps, mitigating any digging into the shoulders or armpits. “We want to eliminate all the distractions a woman feels so she can focus on the exercise,” says Laura Dixon, innovation design director for Whitespace.

So far, the strategy is working. After I left Lululemon, I headed to Granville Island to sightsee and forgot that I was still wearing the Enlite – until I decided to go for a run a few hours later and realized I didn’t need to change bras. Maybe my high-school self was onto something with that 24-7 sports-bra thing after all.

 

The Enlite bra ($98, at lululemon.com) comes in Black, Marvel (raspberry red) and Magnum (grey).

 

READ MORE: The history of the sports bra