Women's running shoes will differ in shape and feel to men's running shoes. it's important to say straight away that what matters is the fit and feel of the shoe. Therefore if a woman finds a man's shoe more comfortable for example, that's probably going to be ok. The main specific differences (other than colour) is that a woman's running shoe is typically a little narrower at the heel compared to men's, this will create a snugger fit. Additionally the cushioning, more recently, has been altered by manufacturers. This reflects the fact that typically a man with size 8 feet will weigh more that a woman with a size 8 feet. As we strike the ground when running with a force approximately 2.5 / 3 times our bodyweight there are different requirements for the feel of cushioning at that point of impact.