Mine is super-tight too. From what I gather from listening to different mum's comments, it makes the movements more easy to feel from the outside, but that's about it. One of my SIL's was amazed at how much she could see Bob stick his knee out the side of my tum. I got the impression from my midwife that it's because I'm a sporty kinda girl and my muscles were in pretty good shape pre-pg.