I saw this video on Youtube that places the Leg extension in the iron grave yard, as one of the most dangerous and worse exercises for the knees.
I’ve actually had ACL ligament surgery on my left knee 1.5 year ago (not cause by this exercise, I fell off a long-board and landed badly at wonderful speed) The ligament was pulled off along with a small piece of bone underneath, the same means you pull off a tree along with its roots from the ground. Luckily the ligament was not cut / ripped so I avoided having an implant and the doctor stapled it back in place along with a plastic stitch connected on the bone. After the surgery it took me around 2 months to start walking again and as a result, my left leg atrophied (Especially the quad muscle) Now the X-Rays & MRI showed that the damage has actually been restored and the doctor tested the knee joint and there is no ligament instability and the left knee is slightly tighter than the right knee now. How ever both the doctor and the physiotherapist recommended me to do Leg Extensions just on the left leg to regain the quad strength and mass back. I’ve been doing this exercise for about a year now and gradually increasing the weights (I can do up to 47KG / 103pounds just on the left leg now) without a problem, so need to I stop it in case it gets injured again? If so, just what various other safer exercises need to I do to strengthen my quad muscles and regain the lost muscle mass?
Thanks in advance!