Mix it up. I've been doing real heavy leg work for 8 weeks, all in 6-8 rep range. Yesterday I didn't squat more than 300lbs and kept the reps high at 20+ and today my legs feel like they've been destroyed!

besides the obvious(having your diet on point, and getting a good nights sleep) change up your workout constantly, do 2 leg days, one day work on hams, and the next leg day focus on quads. i think that is important, your arms get worked with almost everything you do, so its ok to do a combination arm day(biceps and triceps) but your legs dont work unless you work them specifically, so imo, one day is probably not enough considering that they are the biggest muscle on your body. also having more muscular legs has been shown to increase natural testosterone production. as far as a certain rep range being key to getting bigger legs, i dont believe that. do some exercises 6-12, others 10-15, and others 20, but never do the same rep range for each exercise 2 workouts in a row. you want to confuse your muscles as most of us know, and doing the same rep range for every exercise for so and so period of time, doesnt do that. good luck.

Try 2 months:
1. Leg Extensions 3x20
2. Leg Press 3x20
3 Squats 3x20

Do 20 reps not less. I guarantee you results.
Please begin this with your next leg workout, write everything in workout journal and get back to us with updates.
Take pics before and after.

I suggest you a hard program ,but it helps a lot at least on me: do 14-15 sets of heavy squats {free not in the smith machine} 8 reps and low ,and after the machines{leg extention,leg curl&glutes mavhine.BUT,repeat the same training in the afternoon.You must have a good belt and knee wraps.in 2 months my legs were like trees.difficult but if can try it

It also helps if your-a
Knee Gro

Well i have definitely hit on this multiple times, training for hypertrophy, in my thread. Everyone's body is made up of many types of fibers and the ones that are blessed with more type 2, A and B, will naturally grow faster but studies show that you can change these types over time....ex long distance runners vs power lifters.

Now look at the physiques of bodybuilders vs Power lifters. One trains MAINLY for size and one trains MAINLY for power. Have you had the opportunity to watch either? Most power lifters stay within the 1 to 6 rep range of training (Generalization) where as most body builders are in the 8 to 12 range.

Size/Power.....Power, while you definitely need muscle fibers to contract, mainly rely on the tendon strength and source of electricity generated (Brain). When you lift for power you train your brain to fire pulses faster and also in time tell the brain to create more motor units (Think of these as electric poles and the wires as nerves). In the city you have poles and wires everywhere and when power goes out in one place theres another source right there to keep the electric on. What i mean by this is if i took 1 muscle fibre and connected 1 power line to it i can only send so much energy through that particular part of the wire to the muscle therefor not fully being able to contract the muscle 100%. The more i train for power the faster the brain can build thicker wires and even MORE wires and more poles. Now a year after power training, say i dont gain any muscle, i have multiple wires and poles to that one fiber making a single shock contract the whole muscle. These are called nerves and motor units. We can get into muscle synergies and so on and so on but ill keep it basic. This is the basic principle behind Power lifting (Sarcomere).

Hypertrophy or size training is the ability to grow. The only known way to actually create hyperplasia (MORE fibers) is growth hormone but i still need further review on that one but besides that you are made with as many fibers as you are at birth. Hypertrophy is making those fibers grow WIDER. Stretching is very important to keep them as long as possible as they will shorten (tighten) over time as you lift and get older. Anyway bodybuilders lift for size and this requires breakdown of all 3 types of fibers 1 2a and 2b and you do this by multiple sets.Everyone comes up with their own protocol on how many sets per week blah blah blah but a muscle given full nutrition and rest can recover in 48 hours meaning you can lift that same group 2 days later. Technically monday, wed, friday you can do the same thing.

Besides reps there is also pace or whats called time under tension (TUT). This is what will break down the most fibers and also cause the mitochondria to grow inside the cell alone with other intracellular fluid. Im not saying this type of training is the best for sports or functional training, because its not. Its to get bigger not necessarily stronger/faster. When you take your time and squeeze the muscle that you want to work it causes greater sarcoplasmic hypertrophy (Cellular fluid) to form and therefor creating larger muscles.

You can read more into this on my other post or look up sarcoplasmic vs sarcomere hypertrophy.

Conclusion: Spend less time resting (1 minute) between your sets, make sure those 8-12 reps is because thats all you can do in proper form, not just because you hit 8-12 and try to work from 15 to 20 sets for major groups and 10 to 15 for smaller groups although lee priest swears by doing even more reps for arms. If your a beginner this may take some time to build up to this many sets but the body will adapt over time, progressive overload.

Remember keep in mind in order for your body to truly grow you need all the components

protein

exercise

hormones (whether endogenous or exogenous) and honestly this is probably one of the biggest parts...you cant grow if you dont have the testosterone. (Women vs Men is the easiest esample. Yes some women are bigger, stronger, faster but compare their genetic makeup or what they are taking.

and most importantly DEEP rest.

I've found that cause I have long legs I find it hard to get good results from 8-12 rep range. I upped it to 15-20 reps and had great results. I like to have it heavy enough so atleast my last 5 reps are half reps. Also going so heavy that you can only do half reps is a good way to get big gains as it allows you to use bigger weights.
My training partner and I never put the bar down when we're squatting. As soon as he's finished we go back to back and I take the bar off him. Then vice-versa. It gets tough, especially if he only manages 8 squats. My thighs grew 3" in 8 weeks when we started that. That was without any sort of aas.

Hey mate. I personaly do 15-20 on legs. I feel they respond better to higher rep ranges as opposed to upper body. Low rep training does have its benefits however I have gained much better with 15-20 on legs