Not by much and if you keep exercising you can keep a lot of the shape and tone it up. Seek a plastic surgeon who performs hundreds of these procedures, has great reviews and photos, and is an expert in this field.
Have you EVER seen an older woman whose breasts, face or buttocks had the tightness and smoothness of that of an 19 year old? With time and aging, you will sag. Although poor living, smoking, spending time in the sun or tanning booths will greatly increase the sagging, sagging is the price we all pay FOR having the privilege of aging. When you get older you'll understand.