Historical Question on Cavalry Charges

[Midnj]

I acutally saw a video clip on the internet where some lady is jogging along and goes flying when a horse charges in, lowers its head and nails her. She was literally like a bowling pin.. the horse lost almost no momentum at all.

And this was a relatively small horse and a relatively heavy woman, without any extra mass (armoured rider, armor, etc). If there is nothing the horse can impale itself on, I'm sure it would have no trouble literally running over a line of infantry.. I mean if they attacked a mass of infantry the horse might trip over all the bodies at some point, but it should have no trouble knocking armoured infantry around.

And you can convince a person to run into a wall... a person can brace himself and absorb the impact. You probably couldn't convince a person to run into a spear point.