Great demo, thank you for posting it. Does the resistance at the bottom portion of the movement increase with adding weight, or does adding weight only make the top more difficult and the part where you lift with your legs stay the same? My guess is they both increase as it is all connected.
Cautions: people please don't use this machine it is really harmful for your lumbar disc 4 weeks ago i used this kind of machine and then i could nt walk sit or stand up please be careful