Mark. I will be honest. I have a very hard time finding proper sports support. Most bra manufacturers assume that if your cup size is large, then your total ribcage size is proportionally large. Therefore, ones that fit my cup size are too loose in the band to actually provide support. Many sports bras only come in sizes small, medium, large, which does not give the necessary range for the variety of sizes we women come in.
Here is my approach:
Buy the snuggest fitting sports bra I can fit into. Buy different styles of sports bras that have varying features. For instance, I have one that has underwire and good support, but not great coverage. I have another that doesn't give enough support, but covers more flesh. Then I wear TWO bras at the same time. Yes, that may seem like overkill, but I can't stand a lot of jiggle and movement. I will wear the tighter, more supportive bra next to the skin and the one that gives more coverage over that. This really helps a LOT! The other option I do is to wear a sports bra + an athletic top that has built-in support. This achieves a similar affect, reducing lots of excess movement.
Hope this helps your friend!
Also wanted to add the following response from a friend of mine with a specific brand/style recommendation. I confess I have been too cheap to spend $50-$60 on a bra, especially since this brand is not available locally to me, but maybe your pal can find one of these on sale:
The bra I was wearing at camp was the Lululemon “The Bust Stops Here” bra, but I also have one of the Lululemon “Ta Ta Tamers” and it’s also super good. They’re a little on the expensive side ($50/$60) but they wash well and have lasted me since last August - with no signs that they’re giving up any time soon. Lululemon also has good sales occasionally, and my “bust stops here” was like $20 on sale.