1) Squats/presses are most effective for hypertrophy bc they impose the most mechanical tension on the muscle compared to leg extensions
2) Squats/presses will be most effective if you can achieve **sufficient knee flexion** in the hole (quad loaded in stretched position)
3) When lifter can achieve sufficient knee flexion in the hole, it is usually **MORE** than what can be achieved on a leg extension machine
4) If you can’t find a stance/form/technique that allows sufficient knee flexion in the hole with barbell back squats, I rec trying smith squats (one of my faves), leg presses, squat machines
5) Not that big of a fan of hack squats due to inordinate stress on patellar tendon (temdinopathy). I think close stance smith squats are better; allows you to kick hips back a little to decrease load on patellar tendon
6) Ideal squat/pressing exercise allows you to achieve both sufficient knee flexion and hip flexion (glutes—squats and presses more effective than hip thrusts) in the hole
7) Some can’t achieve sufficient knee flexion in hole with barbell squats but interestingly can with leg press
8) The above does not apply to post-ACL reconstruction rehab where leg extensions are more important