^ Depends on how intense the sets are. You only need to do 3 sets a week at 90% to stimulate your nervous system enough to gain strength. The rest of your leg work should be devoted to hypertrophy gains that make your legs bigger and stronger and will assist you in adding strength to your squats and deads.
If you do 6-8 sets twice a week, that's 12-15 sets of intense lifting. You will likely drain your nervous system and find that you are not progressing. Your nervous system needs more time to recover than your muscles.
Also, don't forget to do power exercises during your strength phase to maintain your explosion.
Yes, I will be doing exercises to maintain my explosion.
No, I do NOT need to do only 3 sets of 90% a week to gain strength and devote the rest of my training to hypertrophy. I can do plenty more than 3 sets, and maybe I don't want to hypertrophy? I realize doing 2-4 reps heavy is mainly strength gains, but hypertrophy will come along with it as well slowly, but intentionally aiming for hypertrophy is not my goal.
12-15 sets of heavy lifting a week is fine... Plenty of people do more, and I've done more than this before, and my CNS recovers fine.
