Do you have “PR shorts” or “speed workout bras” that you swear make you faster? Your running clothes just might play a role in your performance.

It’s 4 a.m. in a small hotel room just north of Bear Mountain in New York. The lights are already on, and I’m shifting from mild-mannered reporter to Superwoman — ultrarunning style. My running clothes are laid out: black technical t-shirt infused with minerals purported to aid in body heat reduction, black, short, silky shorts that allow for maximum air flow and minimal chafing, ankle-high black compression socks, and a cycling cap, my nod to personal style versus the function of a running-specific sweat-wicking hat. Really, all that I’m missing is a cape — and that’s exactly what I’m going for.

Ever since I read Chris McDougall’s Born to Run nearly a decade ago, one segment runs through my head as I get ready for every hard run. In describing ultrarunning legend Ann Trason, he wrote, “In street clothes, Ann is a pinch over five feet; in running shorts, she reconfigures to Brazilian model proportions, all lean legs and ballerina-straight back and sun-browned belly hard enough to break a bat.”

While I don’t tan and my abs aren’t that defined, the concept stuck with me: By day, she was your normal college researcher. But on a run, she was a freaking superhero. Without realizing it 10 years ago, this single sentence has shaped what I wear when I run. I might not always be sporting something that looks cool, but my running wardrobe is packed with shorts, tights, bras, and tops that make me feel like I’m heading to the Batcave. (True story: My first triathlon kit was custom-designed with The Flash’s lightning bolt logo on the front.)

But seriously: Beyond simple comfort and functionality, can we improve performance by dressing for the occasion? Essentially, can we fake it ’til we make it with our running clothes? And if so, how the hell do we pick what’s going to make us fast?

What our running clothes say about us.

A 2014 study showed that clothing fit and our perceptions of how fit we (or others are) is linked. The research revealed that participants were more likely to believe athletes wearing tight-fitting apparel ran farther and faster than athletes wearing loose-fitting clothing. The researchers eventually concluded that clothing fit influenced how people feel about their athletic abilities. In 2012, a similar study done with subjects wearing a lab coat showed that donning the coat (putting on a “uniform”) made them more detail-oriented. So, faking it can, essentially, help you make it.

I recently went on a run with a friend who’s new to running and hasn’t played a sport in years. She turned up in baggy sweatpants and a stained t-shirt. It’s not to say that you can’t be a runner in sweats and a t-shirt, but she wasn’t wearing them because they were her only option, she was wearing them, she later explained, because she didn’t want to give off the appearance of “trying to be a runner.”

To be a runner, though, there’s only one thing you need to do: Run. Still, convincing her that she was allowed to wear more running-appropriate attire was a hard sell.

That’s because showing up on the roads or trails to run does require a certain amount of self-confidence. “Confidence is life’s enabler—professionally, intellectually, athletically, socially, and even amorously,” write Katty Kay and Claire Shipman in The Confidence Code: The Science and Art of Self-Assurance—What Women Should Know.

And sports psychology backs this up—in The Brave Athlete, Simon Marshall, PhD, and Leslie Paterson, Xterra pro racer and coach, write, “Athletes with high confidence feel less anxious, relish adversity, set higher goals, try harder, tolerate more exertional pain, feel more in control, are more optimistic and enthusiastic, and do better under pressure.”

How do we create that confidence?

While it’s not as simple as buying a new wardrobe (I wish), clothing can be an easy place to start. Traci Stanard, sports mental consultant and former pro gymnast, knows how important it is to have the right uniform to create the right mindset. It can make you feel professional, competitive, or like part of a team.

“If you train in schleppy clothes and then amp up the clothing and you feel positive in them, there’s a hormonal reaction,” Stanard says. “It has to do with the way you perceive it: knowing what works for you.”

If you’re feeling like you’re in a funk, putting on something new might turn it around.

“Cyclical thinking is a problem: you put on the same cruddy running outfit, you’re going to run the same,” Stanard says. “If you can switch, get out of that cycle, and if you have something in your mind that you can associate with that switch—this thing is going to make me run faster—you can get that result.”

Find your uniform.

How do you want to feel when you’re running? Fast, powerful, smooth? Think of a few adjectives that you want to experience when you head out on your run, and now think about how your most-used running gear makes you feel. Does it make you feel powerful? Or does it make you feel hidden?

You may psychologically distance yourself from the adjective because of a fear of failure, Stanard says. For instance, if feeling powerful conjures up an image of black biker-style shorts and a blazing purple tank top with a crisp white visor, and yet when you actually get dressed to run, you tend to grab baggy sweats and a stained t-shirt, you might be avoiding your power outfit because you don’t believe in yourself.

Take a minute to visualize: You’re on your favorite local running route, midway through. You’re feeling fantastic: Fast, smooth, and on top of the world. Now, zoom out: What are you wearing? It doesn’t matter if it’s shorts and a singlet, tights and a tank top, or a running skirt and a v-neck. It’s not about one uniform being the fastest, it’s about finding your run outfit that makes you feel the best.

If you’re told you should wear a singlet and short shorts but you’re comfortable in tights and a t-shirt, don’t believe the hype.

“If you’re uncomfortable, that’s where your focus will be: on the fact that you’re uncomfortable,” Stanard says. “Whatever you associate positive performance with will make you run faster. Some clothing has different uses: For example, for me, wearing a running skirt means I’m planning on doing errands along with my run or right after and I’m not trying to do my hard workout. I’ve accepted that switch in focus.”

In The Brave Athlete, Marshall even recommends creating an alter-ego (a Batgirl to your Barbara Gordon), so pump up that visualization of you as a happy runner by developing your avatar even more, by adding layers of mantras, pre-run routines, and, of course, specific clothing triggers. Marshall writes, “The great advantage of being an athlete is that we already have good triggers for the transition—our race kit can literally become our costume.”

It’s not just about fit, though certainly finding running clothes that fit correctly and feel comfortable, don’t chafe or constrict is the starting point. But after that, personal preference plays an equally important role.

“Color can even have a huge impact. For some people, bright colors can offer a boost,” Stanard says. You might feel stealthy and pro in all black, while your running partner prefers neon high-vis to feel like a rock star. Find your flavor.

“It boils down to, ‘What’s your focus?’ You just know that you have a hard workout coming when you put on that good running outfit,” Stanard says. “If it’s comfortable, if it’s the colors we want, if it’s nothing we have to think about, we can move on to the next step of performance.”

Take a page from Marie Kondo and prune your running wardrobe. Get rid of the gear that doesn’t spark joy or feelings of confidence. What is the most athletic feeling outfit for you? Whether it looks like that to anyone else doesn’t matter: What you experience when wearing it is what matters. You can be your own superhero.