Is wearing a jogging bra going tohelp 30 years later?

While jogging it may. Help to prevent jiggling. Up to 85% of women in america are wearing an incorrect bra size or a design which doesn't properly support them. Encourage you to go to a specialty bra shop for proper fitting and a bra that will fit your needs. Breast care is important.
Probably not. As women age, it is normal for the breasts to become more flabby and droop. The jogging bra won't prevent this.