It should be noted, however, that large
pectoral muscles themselves will not make
breasts increase in
cup size, because the bra holds the
fat and
glandular tissue of the breast, not the muscle (muscle increase in the
chest, however, may increase the band number part of the
bra size, which is more representative the size of one's chest overall rather than just the
fleshy mounds which
protrude from it.) In fact, a large increase in
muscle mass (in general, not on the chest specifically) will often lead to
smaller breasts because as the lean muscle-to-fat ratio changes, the overall fat percentage is likely to drop, causing
breast shrinkage (i.e., the more fat you have the bigger the breasts, and vice versa, though that isn't the *only* factor involved.)
Breasts may also be made to look larger by such
clothing choices as
empire waist shirts or dresses,
low-cut clothes when paired with a bra that allows for/creates
cleavage, a lack of
bra with a tight shirt or developing more
svelte abs. If there's a specific individual who you want to
impress by appearing to have large(r) breasts, sticking them in their face often works, too.