This might sound stupid, but I recommend wearing sports bras inside out. I have chafing all the time from the seams, but since most are in the inside, if I flip it, there is nothing to chafe.
Fiona was my go to sports bra but their newer sports bras are better. I like the Moving Comfort Juno much better. Better construction, band is different, able to keep straps up better and hides under more tri tops.
Me too. I turn all my sport bras inside out when I wear them. So far, I like the material in the Desoto bras best, although they are pricey.
As to chafing from hr strap, I’ve found that the “new” Garmin strap that has the snaps for the monitor is pretty bad fro chafing in the back where the metal slides hit the back. I switched back to the old black monitor and not had many problems with that.
I have Nike Dryfit Compression. I LOVE THEM! I have never had any problems with them. I am a 34C and wear the XS.
I just bought the new Armour bra by UA. Love it. I’ve worn it for an olympic and half so far with no problems with chafing. I don’t use any body glide either, but I didn’t before. Chafing was never my problem, but I bought the bra because it had very easy to insert padding and I was having issues where everyone could always tell I was cold 
Yup. The Under Armour bra is the shiznit (as the kids say). Doesn’t chafe, holds up the girls, doesn’t give the uni-boob look.
I used to have serious chafing issues from the band of my sports bra - to the point of drawing blood during long runs, marathons, and tris longer than an olympic. The humid summers made it so bad, there were even times that I ran with a ultra thin coolmax tank top UNDER my sports bra to prevent the unhealed chafe from getting worse. I am large busted (36DD) so it’s always been a struggle to find a bra that is well-constructed but didn’t chafe. I had always wondered about the CW-X bras but was reluctant to spend $60 on a bra that I wasn’t sure about. No one I knew wore one and none of the local stores in my small town carried them. After my 3rd marathon in 2007 and another round of bloody chafe, I decided to do more research. It turns out that CW-X is owned by the same company that owns Wacoal - the everyday bras I have been wearing for years because they fit larger busts so well. That did it for me. I found the CW-X Xtra Support Bra on sale on Teamestrogen.com and I have never looked back. No more chafe, I wear it for tris of all distances - it’s great to swim in. The fabric is silky and the support is amazing. I bought another at full price ($60) to switch between workouts. I am still wearing these 2 bras today and they look amazing with no signs of wearing out. Well worth the money. I recommended the bra to my sister this past summer when we were training for the NY marathon. She is large like me but was happy with her Nike bra until she ran 14 miles in the summer humidity. She had some serious bloody chafe. She finished her training and ran the marathon in a CW-X with no chafe. Even in NYC, she had a hard time finding the Xtra Support Bra and ended up ordering it from Roadrunner sports.
I do take some additional precautions during racing. I can’t use Bodyglide - I have sensitive skin and something in it actually makes me chafe worse. I use Mission Athlete Care Anti-chafe cream to prevent wetsuit chafe during the swim. The night before the race, I use Paceline Chamois Butt’r cream and rub it into the support band of my bra. It will absorb in and doesn’t hurt the fabric. Think of it as lotion for your clothes. I also do this in my trishorts and on any seams that might cause a problem. By doing it the night before the race, it has a chance to soak in to the fabric so you don’t feel all greasy when you put on your clothes. Plus who wants to lotion their clothes at 4am on race day?
I hope this helps you. FYI - I have worn Champion and Moving Comfort bras in the past. All chafe except CW-X. Also the bras run true to size. Whatever bra size you wear for everyday bras is what you will wear with CW-X. Just make sure you actually know your bra size. Most women are wearing the wrong size bra.
Good Luck!
+1 for the CW-X. I am a 38c/d and have worn a CW-X bra for years through the Ironman, marathons, etc. They are expensive, but well made. I still use body glide under the band, but almost never chafe. Good luck!
I am also a size 34C and had the same problem on long runs. I’ve tried several brands (including moving comfort) but found that the Road Runner Sports Star Performer Sportek Bra is the best!
http://www.roadrunnersports.com/rrs/products/RRL425/
Even though I wear a 34C normal bra, I get the A/B cup size M in the Sportek Bra and I’ve found that is the best support and fit.
Good luck!
I have a large bust, and workouts were difficult for me because of the bouncing… but sport bra, stops alot of the bouncing and keeps my bust from moving around alot. I was usually a little uncomfortable at the gym because men in particular, would stare… but thanks to sport bra i no longer have to worry about that because I dont move as much as i used to I love sports bra and am so happy with the product and my decision to get it!! 
I am a busty gal 36D and wear the Lynx Sportwear bra. Designed my a busty gall and there literally is no bounce. I have not chaffed wearing it but always use some body glide around my underarms.
very useful thread. I am very sad to say Zoot stopped making my favorite sports bra the Compressrx Ultra Bra so now I have to figure out a replacement… so thanks so much
I was getting such bad chaffing from my sports bras I was using band aids because I never had the down time to let it heal. I eventually turned my bra inside out so there were no seams on my skin. Totally solved the problem. I wear the Nike Pro series of bras but I’m sure you could do the same with any “pull on” sports bra. Hope that helps:)