Women who wear the wrong kind of bra could be damaging their breasts, researchers have warned.
The breast biomechanics team at the University of Portsmouth said poor support could lead to fragile ligaments in the breast being stretched.
They said that during exercise, breasts move up to 21cm (8.26inches), up and down, in and out and side to side - but most bras just limit vertical movement.
And they warned crop-top sports bras did not give enough support.
"There's a social stigma about certain sizes. Many women don't want to be seen as too small or too big and buy a bra that doesn't fit well in order to be what they consider to be a normal size."
Wendy Hedger, University of Portsmouth
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