Back squat, you need those two, as well as properly engaging your erector chain and abs, and depending on if you do high or low squat having the upper body flexibility to hold it. You also have to factor in your body geometry for squats- if you have long femurs and a short torso it will be a real uphill battle vs just doing leg press or even split leg squats.
Any of you guys familiar with the Sheiko training program?
I'm two weeks in after having done RPT for ages and kinda curious what the result is gonna be.
Nice change even though the workouts now take a fair bit longer.