• Wacoal Bra Underwire - Sport (855170): Image 1
  • Wacoal Bra Underwire - Sport (855170): Image 2

Wacoal Bra Underwire - Sport (855170)


The Wacoal Underwire Sports Bra (855170) is the Top-Selling Sports Bra in the U.S! This style's underwire and strap adjustments are positioned on the outside of the sports bra to prevent chafing as well as provide superior fit. Convertible straps give you the option of wearing crisscross or standard style. Designed with Nature, an advanced moisture management fabric that keeps your body cool and dry.


  • Seamless molded cups offer support and stability.
  • Convertible bra straps. Wear crisscross or standard style.
  • Hook and eye back closure.
  • Nature moisture-wicking fabric.


Determine Band Size

  • Wear a good-fitting, non-padded bra and face the mirror.
  • Wrap the measuring tape very snugly around your rib cage, just under your bustline. Make sure the tape is even and parallel with the floor.
  • Exhale and pull the measuring tape as tightly as possible. This is your Rib Cage measurement.
  • If the measurement is odd, add 5". If the measurement is even, add 4". If the measurement is 40" or above, add only 3-4 inches. This is your Band Size.
  • Use this chart as a guideline.
  • Select the Band Size according to your Rib Cage measurement as follows:
Rib Cage 27-28" 29-30" 31-32" 33-34" 35-36" 37-38" 39-41" 42-43" 44-45"
Band Size (USA) 32 34 36 38 40 42 44 46 48
UK 32 34 36 38 40 42 44 46 48
Europe 70 75 80 85 90 - - - -
France 85 90 95 100 105 - - - -
Italy 1 2 3 4 5 - - - -
Australia 10 12 14 16 18 - - - -
  • To confirm the Band Size, wrap the measuring tape loosely around your rib cage, just above your bustline and under your arms. This measurement should equal the Band Size.

Determine Cup Size

  1. Wear a good-fitting, non-padded bra.
  2. Wrap the measuring tape around the fullest part of your bust, making sure the tape is parallel to the floor and lying flat around your body.
  3. This will be a loose measurement. You should be able to easily insert 2 fingers sideways between the side of your breast and the tape. This is your Bust Measurement.
  4. The difference in inches between the Band Size and the Bust Measurement will determine the cup size:
Bust Minus Band 0" 1" 2" 3" 4" 5" 6" 7" 8"
Cup Size (USA) AA A B C D DD/E DDD/F G H
Europe AA A B C D E F G H
France AA A B C D E F G H
Italy - A B C D DD E F FF
Australia - A B C D DD E F FF


Wacoal was founded in 1946 by Japanese Jewelry Designer Koichi Tsukamato after he noticed that Japanese women had started wearing Western clothing and lingerie. Since then, Wacoal has grown to become one of the premier women’s lingerie companies, famous for their focus on superior fit, exceptional quality, extraordinary comfort, and bold innovation. With sizes that range from 30D to 44H, you’re bound to find the perfect lingerie for you!

Wacoal Bra Underwire - Sport (855170) Reviews

Rate and Review this item
Verified Buyer
Best Place for my needs and styles!
By Vene Gregg from Round Rock, Texas from on 9/6/2014
It is difficult for me to find this particular bra in my size and style. It has been a pleasant experience to discover WhatSheBuys always has the size and the style I want! Pros: - The fit, support, and the style. Cons: - Nothing.
Verified Buyer
By Nanci from California from on 1/31/2012
I always wear Wacoal minimizer bras because they don't stretch vertically and provide minimal bounce for my heavy breasts. What I surprise to discover that their version of a sports bra has more vertical stretch than my everyday bra thus allowing more bounce! I'm also not able to adjust the straps as tightly as I would like, and they rub uncomfortably on my back and the excess material sticks out. I'm usually such a Wacoal fan that I just ordered their bra online assuming it would be a well designed sports bra, but I've been disappointed.
Verified Buyer
Most comfortable sports bra I've ever worn
By Teresa from Central Ohio from on 4/17/2011
I guess you do get what you pay for, because I've been working out regularly for over a decade and I've purchased all kinds of sports bras. A saleslady at Macy's recommended this bra to me, and I really hesitated over the price. But after trying it on, I decided to give it a try. I love it! I'm a D, and bounce is not a problem for me in this bra. I just hope they don't discontinue it anytime soon.
Verified Buyer
Review for Wacoal Bra Underwire - Sport (855170)
By yona hermann from on 1/14/2011
Very comfortable. Looks like I am putting it on backward but I guess I am not. Follow the labels.
Verified Buyer
Review for Wacoal Bra Underwire - Sport (855170)
By Anonymous from on 10/11/2010
My favorite sports bra--expensive but worth it. For a C cup, it works for my high impact sport of horse back riding. I wear it standard style
Verified Buyer
Review for Wacoal Bra Underwire - Sport (855170)
By Lisa C. from on 6/24/2010
I am a DD and had a hard time finding a supportive, comfortable sports bra. This one is wonderful. I highly recommend it.
Verified Buyer
Review for Wacoal Bra Underwire - Sport (855170)
By Anonymous from on 5/28/2010
I'm a huge wacoal fan, but I didn't love this one. I'm a 32 DDD and I found that it gave my ribs great support, but didn't eliminate the bounce factor as much as I would have liked it to. If it weren't so tight around the rib cage, it would be a great every day bra, but for me, it dug a little too much for a daily wear bra. Though it's probably a wonderful bra for a D cup or smaller. The sport bra Wacoal made about 5 years ago was perfect and I wish they still made it.
Verified Buyer
Review for Wacoal Bra Underwire - Sport (855170)
By Rebecca Stepaniak from on 5/23/2010
Nice, sturdy, comfortable. I am a DD and there is still bounce with this but that may be inevitable. Definitely pricey but doesn't seem more so than equivalents.
Verified Buyer
Review for Wacoal Bra Underwire - Sport (855170)
By Neema from on 1/18/2010
Most comfortable sports bra on the market! I have always shyed away from underwire bras but let me tell you - they have perfected this one! Tremendous support, durable AND comfortable!
Highly recommend