chairseat?!?!?

I hope this doesnt make me sound really dumb, :/ but I'm really confused on what a chairseat is..
I've been trying to look at some pics online but it's not helping much.. can someone explain?
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The Art of Classical Riding--Achieving the Seat

When riding your ear, shoulder, hip and heel should all line up if you were to draw a straight line down your body. In the photo on the website above you'll see that his heels are too far in front of him.

Very basically, your toe is in front of your knee. Your toe should be behind your knee, forming that constantly talked about heel-hip-shoulder line.

Ahh this makes a lot more sense. So it's almost always the heel being too far forward? Not aligning with the hip shoulder ear line?
Posted via Mobile Device

Oui! Ca c'est correct!