Open chain vs. Closed

What is an Open Chain exercise? and a Closed Chain exercise?

Feel free to give several examples of both.

My first reply sucked… my next one is better.

I’ve seen pullups referred to as Closed Chain and pulldowns as Open Chain.

I need to understand this concept more fully.

An easy way to think about it is if you are moving the weight towards or away from your body, it is open chained, and if you are moving your body away from the weight/resistance or fixation point, it is closed chain.
In pull-ups, you are moving your body toward and away from the fixation point, or where your hands grasp the bar. In pull-downs you are moving the bar towards and away from your body, thus making it open chain.
Squats are closed chain because you are moving your body and the weight against the resistance or fixation point, i.e. the floor.
Hamstring curls are considered open chain because you are moving the weight around your body. Glue-ham raises would be considered closed chain because you are moving your body around the contact point, the pad and toe plate.
Push-pus would be closed chain because you are moving your body towards and away from the point of fixation point or resistance, the floor. Bench press would be open chain because you are moving the weight towards and from the body.
I can give some more examples if you need any, but this should hopefully clear things up for you. If not post again and I will try to explain a little better.

Dr. Steindler wrote:

"We designate an open kinetic chain a combination in which the terminal joint is free. The waving of the hand is an open kinetic chain in which the action of the shoulder joint, the elbow joint, and the wrist joint are successively involved.

A closed kinetic chain, on the other hand, is one in which the terminal joint meets with some considerable external resistance which prohibits or restrains it free motion. Eventually, the external resistance may be overcome and the peripheral portion of the joint may move against this resistance, for instance, in pushing a cart or lifting a load; or the external resistance is absolute, in which case the proximal part moves against the peripheral, as for instance, in chinning oneself on a horizontal bar; or the limitations of the muscular effort may assert itself both peripherally and proximally and may be unsurmountable, in which case no visible motion is produced. Only in the latter instance is the kinetic chain strictly and absolutely closed.

However in common use we apply the term to all situations in which the peripheral joint of the chain meets with overwhelming external resistance."

Very good, thanks.