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Home / Sports Bras / Catalyst Sports Bra - Last Call
Last Call

Catalyst Sports Bra - Last Call

$39.00 CAD

$85.00

54% off

Our most supportive sports bra

Eliminates bounce by 76%

Ventilation for increased airflow

Full coverage design

Front view of model wearing the Catalyst Sports Bra, highlighting the neckline, strap design, and smooth silhouette

Adecia is a 34D wearing KNIX M+

View of Catalyst Sports Bra shown front-facing against a light gray background
Back view of model wearing the Catalyst Sports Bra, highlighting the neckline, strap design, and smooth silhouette

Adecia is a 34D wearing KNIX M+

View of Catalyst Sports Bra interior ventilation for increased airflow
Front view of model wearing the Catalyst Sports Bra, highlighting the neckline, strap design, and smooth silhouette

Adecia is a 34D wearing KNIX M+

Size Chart Conversion from Original Sizing

Adecia is a 34D wearing KNIX M+

Color: Blue Light Limited Edition

Size:

True to Size

•

Size:

Size and Fit Guide

Free Shipping on orders $100+

Shipping

Shipping

Processing Timelines

Please allow 1-2 business days for our warehouse team to pack and ship your order. During peak periods such as sales, holidays and product launches, please allow up to 4 business days for us to process your order.

Delivery Time

For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines vary depending on location and do not include processing times.

Shipping Charges

Orders over $100* CAD = Free Shipping (2-6 business days)

Orders under $100* CAD = $12 CAD Shipping (1-3 business days)

Orders delivering to NWT, Nunavut and Yukon are subject to $20 delivery fee.

*After discounts, before shipping and taxes.
Last Call Return Policy

Sale & Last Call

Our Sale Policy

Here's how returns and exchanges work for sale items.

  • Items discounted 30% or less are eligible for a size exchange or store credit.
  • Items discounted above 30% are final sale. No refunds, store credits, or exchanges.
  • Not sure where your item lands? Chat with us and we'll check for you

Still have questions? View our full policy here.
Rewards Members Earn 39 Points

"It’s the only sports bra for bigger boobs I've tried that keeps bounce to a minimum when running."

- SELF

High Impact Support

You are in control of your performance with our most supportive, full-coverage sports bra.

Feels Made For You

The traditional adjustable hook and eye back closure, featuring five rows, allows you to find the perfect fit easily.

Functional Style

The breathable, moisture-wicking fabric and ventilation in the front help you stay cool throughout your workout. Made with encapsulated cups for maximum support and a locked-in feel, this bra reduces overall breast movement by 76%*.

*During treadmill running; based on the University of Portsmouth Research Group in Breast Health study, 2018.

Zoom

Adecia is a 34D wearing KNIX M+ | Front view of model wearing the Catalyst Sports Bra, highlighting the neckline, strap design, and smooth silhouette | Blue Light
Adecia is a 34D wearing KNIX M+ | Back view of model wearing the Catalyst Sports Bra, highlighting the neckline, strap design, and smooth silhouette | Blue Light
Adecia is a 34D wearing KNIX M+ | Front view of model wearing the Catalyst Sports Bra, highlighting the neckline, strap design, and smooth silhouette | Blue Light

How to Choose?

Essential

  • • Days you don’t need leak protection. Everyday freshness and moisture wicking.
  • tsp
    0 tsp

Heavy

  • • Extra peace of mind. For the first days of your cycle, light bladder leaks, or a full night's sleep without a leak.
  • tsp
    about 8-14 tsp
  • pad
    about 1.5-3 regular pads
  • tampon
    about 4-7 super tampons
  • cup
    about 1.5-3 menstrual cups

Light

  • • Daily freshness. For sweat, discharge, period spotting, or backup protection.
  • tsp
    about 1-3 tsp
  • pad
    about 1-3 pantyliners
  • tampon
    about 1-3 regular tampons
  • cup
    about 0.5 menstrual cups

Moderate

  • • For mid-cycle flow, surprise cough or sneeze leaks, or a really sweaty spin class.
  • tsp
    about 4-8 tsp
  • pad
    about 1-1.5 regular pads
  • tampon
    about 2-4 super tampons
  • cup
    about 0.5-3 menstrual cups

Ultra

  • • Ultimate peace of mind. For the heaviest period days, light bladder leaks, unexpected postpartum flow, or overnight protection.
  • tsp
    about 15-20 tsp
  • pad
    about 1.5-2.5 super pads
  • tampon
    about 7-11 super tampons
  • cup
    about 2-3 menstrual cups
HIGH IMPACT SPORTS BRA

Elevate your performance. Engineered for movement.

The encapsulated cups provide maximum support for a locked-in feel that reduces overall breast movement by 76%*.

High Impact Support

Combines breast encapsulation and compression for maximum impact support.

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4.4
Rated 4.4 out of 5 stars
Based on 5,896 reviews
Reviews Summary
Customers say this sports bra provides excellent support and comfort, particularly for larger busts. Many appreciate the wide straps and wireless design that holds everything securely during workouts and daily wear. Users frequently mention wearing it all day due to its comfort level. However, several note sizing challenges with the newer version, finding it runs smaller than expected and requiring sizing up. Common feedback includes concerns about strap placement and adjustment issues - some straps slide down or loosen throughout the day. A few mention durability problems with glue separation and strap hardware breaking over time. While most praise the supportive fit, some experience gaping at the armpits or find the material feels heavy compared to other sports bras.
89%would recommend these products
ComfortRated 4.5 on a scale of 1 to 5
FitRated -0.4 on a scale of minus 2 to 2
SupportRated 4.6 on a scale of 1 to 5
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5,896 reviews
  • Rated 5 out of 5 stars
    8 hours ago
    Knix Catalyst

    I wear this for cycling . Very comfortable and sweat absabsorbent

    EC
    Elizabeth C.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra Pink Party / M
    Was this helpful?
  • Rated 5 out of 5 stars
    6 days ago
    No bounce!

    I am large breasted and have difficulties finding a sports bra that accommodates my asset without straps digging into my shoulders while reducing front end mobility. I love how the catalyst packs in my boobs and keeps them in place. At first I had doubts about the short and wide straps not having any give but that’s what prevents the bounce when I’m running. The generous cut also keeps sideways spillage under control. This bra is so comfortable that I can wear it all day long.

    SC
    Sibylle C.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra Pink Party / L+
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Comfy Fit

    I enjoy this sports bra and have the light blue as well.

    SG
    Shawna G.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra Pink Party / L+
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Great purchase

    Love this Sports bra. Great support and looks great

    LJ
    Linda J.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra Pink Party / XXXL+
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    This large chested girl is happy!

    I am generously endowed in the chest. For most of my adult life, I have avoided sports or pasttimes that require me to run as the chest bounce was really uncomfortable.

    Then we got a dog and decided to show him. I now literally run around a ring with my large dog on a leash and make him look pretty. This bra has saved me! The comfort of this bra and the support is amazing! And the fact that it doesn't do the uniboob smoosh is a really nice detail.

    JR
    Janet R.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra Black / XXL++
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    Support and Comfort

    So comfortable for moving without bouncing and holds the girls up! I am using a band extender till it relaxes a little bit.

    MA
    Marianne A.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra White / XL++
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    Great sports bra

    I'm really happy with this bra, that is not underwire. I purchased three so far and have told friends about it.

    LB
    Lori B.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    Running Holy Grail

    I’ve been running for years in some pretty terrible sports bras and knew it was time to invest in a good one. The staff at the Westboro store helped me picked The Catalyst and it is incredible. Everything stays in place and I honestly forget I have it on. Will be buying a few more so I’m never without it on any run.

    LA
    Leanne A.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra Black / M
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    Love this

    So comfortable and supportive. I love that it's not a pullover.

    MD
    Marie D.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra Black / XXL+
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    Catalyst sports bra

    Excellent! Provides full support.

    IK
    Indira K.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra - Last Call Blue Light / S+
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    Best running Bra

    I wear 34DDD, having a bra that supports me during running has been a journey. This bra is amazing. I suggest giving it a try at the store as I needed size S+ while with other Knix bras I wear M++

    HK
    Huda K.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    Catalyst bras

    I have bought these bras for my Zumba and cardio classes and they are awesome! I highly recommend if you want a quality product and support!

    LH
    Linda H.
    Verified Buyer
    Reviewing
    Catalyst Sports Bra
    Was this helpful?

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