2 legs at a time. But its a independant machine so each leg has its own place for weight. Ya not a big fan of heavy leg extensions. I just try to go slow and REALLY SQUEEZE the shit out of my quads. I never lock out either and I never go down all the way. If you imagine 4 sections of the range of motion, I keep it to the middle 2, slightly into the last section of the range of motion short of lock out. I think the lock out is what puts so much pressure on the knee and any joint, tendon for that matter.
I think of leg ext more of as a warm up and a finisher.
I think of leg ext more of as a warm up and a finisher.