I'm 19 years old and I have saggy breasts. Would exercising help this or is it too late for me?

It is difficult to give you specific advice without a consultation.  However, generally, once your breasts have sagged there are no methods to a) lift the nipple and b) tighten the skin without surgery.  Your first and most important step is to find a qualified plastic surgeon to evaluate your breasts.

Far more important than the technique is the skill and experience of your plastic surgeon. Choose your surgeon rather than the technique and let them explain why one technique may be better than another.  See the below link on some suggestions on finding the most qualified Plastic Surgeon for a BBL Always insist on a board certified plastic surgeon.
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