The ISS is orbiting, it's falling sideways fast enough to miss the earth. It's effectively in freefall, so although objects at 400km altitude are subject to 80

The ISS is orbiting, it's falling sideways fast enough to miss the earth. It's effectively in freefall, so although objects at 400km altitude are subject to 80% of the gravitational pull you experience on the ground, the astronauts don't notice it because they're falling sideways at the same speed as the ISS. Edit: I just noticed that the post you were replying to included pretty much the exact same information I did, so I apologise if what I've said hasn't helped.