can I do different rep ranges like 3-5 and 8-12 in for squats to get both size and strength?
yes you can
Edit* you can also do 20+ rep sets. I would suggest this if you do not like yourself
The answer to this question lays in whether you are a novice and whether you want optimal gains.
my last leg workout I did 4 sets of 5 and finished squats off with sets of 8-12 is this good or should I focus on one rep range
I’d experiment on what works for you and when you hit stand still points (plateaus). So how about try 5x5 for 4-6 weeks, see how you feel and then mix it up and try 10-12 reps instead. Both will increase size and strength, just make sure the reps are getting better and the weight are getting heavier
I would pick a proven program and do whatever rep ranges are in said program.
alright thanks for the help
Just to add, size and strength aren’t mutually exclusive.
Eventually it would be good to find a sweet spot. Can’t really tell you what it is, as it is for you to experiment with and whatnot.
Mostly submaximal stuff, with some sort of progression will do you good in the size and strength departments. Whatever percentage allows you to get the job done, with some power behind it in 3-5, or 6-8 rep and set range. Divvy them up accordingly, rotate them, all that Jazz.
Bring up lagging parts as well. Secondary stuff, whatever you wanna call it.