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Catalyst Sports Bra
High Support
Catalyst Sports Bra
$85.00
CAD
Buy 2 Bras Get 10% Off
Our most supportive sports bra
Eliminates bounce by 76%
Ventilation for increased airflow
Full coverage design
Size and Fit Guide
Use Our Calculator to Find Your Traditional Bra Size
Step 12 of 2
Your Results
Measure Your Under Bust
Measure Your Full Bust
Wearing an unpadded bra, wrap a measuring tape around the top of your ribcage. You’re looking for a snug fit - so we recommend tightening on the exhale and noting the smallest measurement to the decimal.
Wrap the measuring tape around the fullest part of your chest, making sure the measuring tape is paralell to the floor. Relax your shoulders and measure where it falls.
At Knix, your size is
Still have questions? Ask our virtual assistant about finding the perfect fit.
Still have questions? Reach out to info@knix.com to learn more about our sizing.
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Product Description
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
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How to Choose?
Essential
- • Days you don’t need leak protection. Everyday freshness and moisture wicking.
-
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.
-
about 8-14 tsp
-
about 1.5-3 regular pads
-
about 4-7 super tampons
-
about 1.5-3 menstrual cups
Light
- • Daily freshness. For sweat, discharge, period spotting, or backup protection.
-
about 1-3 tsp
-
about 1-3 pantyliners
-
about 1-3 regular tampons
-
about 0.5 menstrual cups
Moderate
- • For mid-cycle flow, surprise cough or sneeze leaks, or a really sweaty spin class.
-
about 4-8 tsp
-
about 1-1.5 regular pads
-
about 2-4 super tampons
-
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.
-
about 15-20 tsp
-
about 1.5-2.5 super pads
-
about 7-11 super tampons
-
about 2-3 menstrual cups
Comparison Chart
Catalyst Sports Bra
Maximum support
Clasp back closure
Reduces bounce by 76%
Restore Sports Bra
Light support
Padding-free
Pullover style
Momenta Racerback Sports Bra
Medium support
Mesh underband for ventilation
Bra top with sewn-in padding
Longevity Sports Bra
Light support
Bra top with bonded-in cups
Pullover style
HIGH IMPACT SPORTS BRA
High Impact Support
Reduces Breast Movement
Tri Flo Ventilation
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Recently Viewed
Reviews Summary
Generated by AI from 100 most recent customer reviews
Last updated 3 months ago
Customers say this sports bra provides excellent support and comfort, especially for larger bust sizes. Many appreciate the wide shoulder straps and wire-free design that keeps everything secure during workouts and all-day wear. Users frequently mention the breathable, soft material and adjustable fit. However, several note sizing challenges with the newer version, finding it runs smaller than expected and requiring sizing up. Common concerns include straps that may slip or loosen throughout the day, and some experience gaps around the armpit area. While many praise its durability and long-lasting support, a few mention quality issues with adhesive coming apart over time. The bra receives mixed feedback on the recent design changes, with some preferring the previous version's fit and strap system.
90%would recommend these products
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5,318 reviews
- Rated 5 out of 5 stars2 days agoGreat purchase
Love this Sports bra. Great support and looks great
LJLinda J.Verified BuyerReviewingCatalyst Sports Bra Pink Party / XXXL+ - Rated 5 out of 5 stars2 days agoThis 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.
JRJanet R.Verified BuyerReviewingCatalyst Sports Bra Black / XXL++ - Rated 5 out of 5 stars4 days agoSupport 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.
MAMarianne A.Verified BuyerReviewingCatalyst Sports Bra White / XL++ - Rated 5 out of 5 stars4 days agoGreat sports bra
I'm really happy with this bra, that is not underwire. I purchased three so far and have told friends about it.
LBLori B.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars5 days agoRunning 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.
LALeanne A.Verified BuyerReviewingCatalyst Sports Bra Black / M - Rated 5 out of 5 stars3 weeks agoLove this
So comfortable and supportive. I love that it's not a pullover.
MDMarie D.Verified BuyerReviewingCatalyst Sports Bra Black / XXL+ - Rated 5 out of 5 stars1 month agoBest 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++
HKHuda K.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars1 month agoCatalyst 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!
LHLinda H.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars1 month agoSupportive and comfortable!
I’ve been wearing the Catalyst bras for years. I’m a large breasted woman and this bra is the only one that keeps the ladies in control…no digging in, no bounce, beautiful line and well supported. I wear the Catalyst every day and cannot go back. Comfortable and supportive, just the best!
CHCarol H.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars1 month agoSupportive and comfortable!
A great bra thst offers great support and os also very comfortable. The wider straps are grest too
RWRita W.Verified BuyerReviewingCatalyst Sports Bra White / XL - Rated 5 out of 5 stars2 months agoCatalyst LT Sports Bra - L+/G+
I absolutely love it. I will wear it for everyday use as well! Great support!
DFDonna F.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars2 months agoTrue love!
I love my new catalyst sport bra. I love the support, the look, the comfort. Love everything about it.
KVKarine V.Verified BuyerReviewingCatalyst Sports Bra
