Meet the Founders of PAIRR Running Socks

“The first product we ever thought of designing was ‘Avril Lavigne singing powder’—a powder you would take to magically make your voice sound like your favourite artist.”
— Michelle Krezonoski, Co-Founder of PAIRR

Nestled in a remote corner of Northern Ontario, twin sisters Kim and Michelle Krezonoski grew up with a shared dream: one day, they would create and design their own business.

Instead of Disney princesses and Barbies, the sisters found themselves fascinated by entrepreneurs. They idolized Mary-Kate and Ashley Olsen and watched the earliest seasons of The Apprentice, then a brand-new business show airing on satellite TV.

“We were always creating and designing with whatever resources we had,” Kim says. “Our first ‘products’ were dresses made from pillowcases.”

There was only one problem: neither sister knew how to sew, and they didn't have a sewing machine.

“So we would literally hot-glue ourselves into the dresses,” Kim laughs. “Our fashion career ended when our mom started running out of pillowcases.”

The pillowcase dresses were only the beginning.

“Our biggest business adventure as kids was designing flip-flops and shoes out of paper and duct tape. Our mom had a vacuum with a hose that leaked, so she always kept duct tape around to repair it. We would trace our feet onto paper, cut out the ‘insole,’ and cover the bottom with duct tape for grip and durability. Then we'd fold the tape in different ways to create straps. We even made ‘heels’ by layering the duct tape together.”

From Science and Competitive Running to Entrepreneurship

Despite their early fascination with business and design, Kim and Michelle initially took a different path.

The sisters pursued science, completing bachelor's degrees in Biology and Chemistry before earning master's degrees in Anatomical Science from Queen's University.

“I think we didn't choose business initially because there seemed to be too much risk and too much to lose,” Michelle says. “We didn't come from wealth, we supported ourselves through school, and we didn't think starting a company was possible until we had saved for a number of years.”

So they saved.

They didn't know exactly when they would start a company, or even what they would create, but they knew something changed whenever they began brainstorming products and building ideas. Work suddenly collided with passion.

At the same time, running remained a major part of their lives.

Kim and Michelle are lifelong competitive runners who have raced track, cross-country, indoor and outdoor track, and NCAA Division II collegiate competition before eventually transitioning to the marathon.

Their training led them to marathon personal bests of 2:36 for Michelle and 2:37 for Kim. The sisters later finished 23rd and 26th at the 2024 Boston Marathon.

“We've been runners for most of our lives,” Michelle says. “Transitioning to the marathon was definitely an adjustment, but it also felt natural. When you're passionate about the sport, it's exciting to challenge yourself with a new distance and a completely different style of training.”

Running would eventually become the intersection between their experience, curiosity, and desire to build something of their own.

More Than a Decade of Running Led to PAIRR

In the winter of 2023, Kim and Michelle decided to enter the running apparel industry.

More specifically: running socks.

“We chose socks because, from the perspective of lifelong runners, we felt there was an opportunity to do something different,” Michelle says.

After years of training and racing, the sisters had worn countless pairs of running socks. They saw an opportunity to combine performance-focused materials with a cleaner, more intentional aesthetic.

“We wanted to create socks you would reach for when running, walking, traveling, and living your everyday life—but that you could also trust when you're standing on a race start line.”

That idea became PAIRR.

The goal wasn't simply to make another running sock. It was to understand what runners actually need from the layer sitting directly between their feet and their shoes and then obsess over every detail.

The Beginning of PAIRR: The Start Line

Finding the right manufacturer became one of the most important decisions in developing PAIRR.

Kim and Michelle carefully researched materials, manufacturing techniques, and production partners before choosing a European manufacturer with more than 30 years of experience producing socks.

“Selecting a manufacturer was simple and challenging at the same time,” Kim says. “It was simple because we knew exactly what we wanted.”

Their priorities included access to premium fabrics and knitting technology, a manufacturing partner willing to experiment with fit and construction, responsible production practices, and the ability to eventually scale PAIRR globally.

“The difficult part was finding a partner that aligned with all of those priorities.”

PAIRR's socks are manufactured in Europe, where the team continues to work directly with its manufacturing partner to test materials, refine construction, and improve each collection.

What Is the Best Fabric for Performance Running Socks?

When developing Collection 001 and PAIRR's LANE fabric, Kim and Michelle started with a simple question: What problems do runners commonly experience with their socks?

They wrote down five main points from experience: Moisture. Heat. Fit. White socks turning grey. Blisters.

Then they asked a second question:

Could we develop a fabric and sock construction that addressed these problems without sacrificing comfort, aesthetics, or performance?

That process led to LANE.

PAIRR's LANE fabric uses a 93% polypropylene and 7% elastane blend with 0% cotton.

Before releasing it, Kim and Michelle tested the material across hundreds of runs and dramatically different conditions—from approximately -40°C Canadian winters to +40°C summer heat.

Rainy runs. Humid runs. Morning runs. Evening runs. Easy miles. Workouts. Training shoes. Carbon-plated supershoes.

The goal was to understand how the material behaved when runners actually used it.

Why Polypropylene Is Used in PAIRR Running Socks

Polypropylene was selected as the primary fiber in LANE because of several properties that make it particularly interesting for performance running socks.

Most importantly, polypropylene is hydrophobic, meaning the fiber itself absorbs very little water.

“The hydrophobic nature of the fabric was incredibly important to us,” Michelle explains. “Rather than relying on the fiber to absorb sweat, moisture can move along the fiber surface and through the knit structure, where it can evaporate.”

Polypropylene is also exceptionally lightweight and can be solution-dyed, meaning pigment is incorporated during fiber production rather than simply being applied to the surface afterward. This can contribute to strong colorfastness.

For runners, however, the most important question isn't simply what a fabric is made from.

It's how the fabric, knit structure, ventilation, cushioning, and fit work together.

What Makes a Good Running Sock?

When we break down the technology behind a performance running sock, we think about four major components:

1. Fabric

PAIRR uses performance-focused fibers selected according to the purpose of each collection.

In LANE, hydrophobic polypropylene fibers help minimize moisture absorption while creating an exceptionally lightweight sock.

2. Airflow

PAIRR's HEXVENT™ ventilation zones use small hexagonal openings strategically positioned to increase ventilation through areas of the foot where heat and moisture can accumulate.

The goal is simple: create more opportunities for heat and moisture to escape.

3. Knit Construction

Different fibers and knit structures serve different purposes.

For example, PAIRR uses COOLMAX® technology in Collection 002: THE 400. COOLMAX® fibers use a multi-channel geometry designed to help transport moisture along the fiber surface through capillary action.

Rather than choosing a material because it sounds technical, PAIRR evaluates how each fiber contributes to the intended function of the sock.

4. Fit

A performance running sock needs to move with the foot.

PAIRR socks incorporate features such as strategically positioned ventilation, targeted cushioning through the heel and toe, a contoured ribbed arch, and elastane transition zones designed to accommodate multidirectional movement.

The objective is a secure, performance-oriented fit without unnecessary bulk.

Designed by Runners. Tested Through Real Miles.

For Kim and Michelle, developing PAIRR didn't end when the first product went into production.

Testing is an ongoing part of the process.

PAIRR began with hours of research into performance textiles, athletic socks, foot biomechanics, moisture management, and fiber properties. Today, the team continues to evaluate fabrics through laboratory testing, wear testing, analysis, and most importantly—real miles.

There isn't a single day when the goal is simply to create another sock.

“We aren't interested in releasing another cotton/polyester sock just because we need something new to sell,” Kim says. “We want PAIRR to be a one-of-one brand: a brand where every sock is released with purpose and every design decision has an intention behind it.”

The Future of Running Sock Fabric at PAIRR

Performance textiles continue to evolve, and PAIRR intends to evolve with them.

Future collections will explore new fibers, constructions, climates, distances, and use cases while staying grounded in why PAIRR was founded. From moisture management and temperature regulation to durability, cushioning, fit, and feel, PAIRR continues to investigate how seemingly small changes in yarn and construction can change the experience of a running sock.

Collection 003: The Next Miles for PAIRR

“We tend to drop a lot of hints about upcoming collections—maybe a little like Taylor Swift,” Kim laughs.

PAIRR's guiding idea remains Socks That Fuel Confidence.

“That idea sits behind every collection, photoshoot, and decision we make for PAIRR,” Kim says. “All I can say about what's next is that a lot of dogs and good energy will be involved in our next photoshoot.”

PAIRR currently offers three core cuff heights—crew, quarter, and ankle—with the collection continuing to expand.

“We listen closely to what runners tell us,” Michelle says. “We're continuing to explore new cuff lengths, fabrics, styles, and colors, but we don't want to release something simply for the sake of having more products. We want every PAIRR to have a reason for existing.”

From paper-and-duct-tape shoes in Northern Ontario to marathon start lines and performance textile development, the underlying idea hasn't changed very much.

Kim and Michelle are still designing things together.

They just don't need their mom's duct tape anymore.

Two is a PAIRR.