Hey, I have had recurring knee pain and have a lateral meniscus tear which is not too bad but I have been told to be watchful of the heavy exercises like Squats, Deadlifts etc. I was wondering if i can substitute the Back Squats with Hack Squats ? I have this machine at my gym and it might be the same feel except the core stability is not required. I do use leg press and leg extensions a lot along with Tib raises to get the knee area and quads stronger, the injury is from tennis. Another question was on Pre-workout , just in general yay or nay ? Thanks in advance!