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Catalyst Sports Bra
High Support
Catalyst Sports Bra
$78.00
USD
Buy 2 Bras Get 20% 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
What our customers are saying
Generated by AI from 100 most recent customer reviews
Last updated 4 months ago
Customers say this sports bra provides excellent support and comfort for larger busts, with many wearing it all day. The wide straps and molded cups offer secure hold during high-impact activities like running and weightlifting. Many reviews mention the soft, breathable fabric and flattering fit without underwire. Common feedback includes concerns about sizing changes, with several noting the need to size up from previous versions. Some experience issues with strap placement and adjustment, particularly with newer models where straps may loosen or slip. While most praise the durability and long-term wear, a few mention quality concerns with adhesive or hardware over time.
90%would recommend this product
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5,326 reviews
- Rated 5 out of 5 stars3 minutes agoCatalyst sports bra
Great fit, comfortable, good support.
KPKelly P.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars1 hour agoA must have for horseback riding!
I got this bra for my riding lessons to help with the "bounce" while trotting, and it works like a CHAMP. I am so impressed at how well this bra hold me in!
MMMeagan M.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars23 hours agoBest Sports bra ever!
And now that they come in M++, they fit my 34F chest better. So comfortable that I often wear as a daily bra—one that is ready for action yet easy to wear all day.
Please keep the cute and colorful patterns coming!
KMKimberley M.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 starsYesterdayGreat, supportive bra
I have several of these bras. I know this is a "sports bra" but I wear it all the time. It is supportive and has good coverage.
AGAlison G.Verified BuyerReviewingCatalyst Sports Bra - Rated 1 out of 5 stars3 days agoShort bodied fit
Less comfortable - needs a larger circumference and shorter body length than I have. Very disappointed with an online order. Recommend trying before buying.
KLKaranne L.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars4 days agoPerfect support bra
I love the catalyst bra it fits well and has great support
JOJennifer O.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars5 days agoGreat
Perfect fit
KFKrista F.Verified BuyerReviewingCatalyst Sports Bra - Rated 3 out of 5 stars5 days agoNice Bra
This bra is super comfortable for day to day. But as a sports bra - not so much. For larger boobs I didn't find this gave any real support in more bouncy workouts. Running, dancing, aerobics etc there was just no real support. There's no support under the breast, if there was a band under that would make a huge different. I tried adjusting the straps but nothing was making a difference. She'll just stay as a work day bra.
MRMichelle R.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars6 days agoMost comfortable sports bra
This sports bra is really comfortable and so light you feel like you almost have nothing on. I’ve owned many other brands but Knix tops them all.
JBJocelyne B.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars1 week agoLove the bra!
Great support!
MBMarguerite B.Verified BuyerReviewingCatalyst Sports Bra - Rated 5 out of 5 stars1 week agoGreat sports bra that fits!
Love this bra and the size! It fits and is comfy - could wear it all day!
HSHamreet S.Verified BuyerReviewingCatalyst Sports Bra - Rated 1 out of 5 stars1 week agoDisappointing
I had high hopes for this bra, but it is not good. The strap adjusters do not stay in place so by the time you do any movement the strap are at their longest which does not help with the support I wanted for running. Unfortunately missed the return window of would have sought a refund. First and last Knix bra purchase.
CHChristy H.Verified BuyerReviewingCatalyst Sports Bra
