Saggy Boobs (serious question)

Hi ladies,

I would really like to know if there are older women out there (40s, 50s, more?) who have managed to age WITHOUT their breasts sagging by use of exercise, etc. I am 31 and may've just imagined it, but my proudly perky little B cups look like the might be leaning toward the floor. :'-( I may just be imagining it, but I really want to see if I can get around this if I get more disciplined with strength training. Any dancers out there, yoga instructors, whatever works???

Background: I'm 31, a few pounds overweight, but not much, still nice figure, and I have always done some weight training, even if just once a week for upper body. I've always lifted for arms, back and chest, chest specifically to keep my breasts up where they should be. Because I am now wondering if they might be thinking about getting more aquainted with my belly button, I'm wondering if I added yoga, pilates, dancing, some stretching, elongating, muscle toning thing to my regimen and got serious about it if I can avoid saggy boobs! I've never had kits.

I look forward to any replies!

Thx,
Roooth