Hi
@Ny Wc, I personally have been on a low rep hypertrophy program since August and have seen constant gains of a pound a week easily, more when I can manage to eat enough. I have found reps of 5 and even reps as low as 3 have been great for building muscle, while also gaining some strength. What I have found to be key is to keep rest time to around 2 minutes, any longer just allows for too much recovery between sets and to do at least 5 sets of an exercise. I tend to find 5x5 and 8x3 necessary, any less and it just doesnt trigger growth, so you are looking at the ball park of 25 reps per exercise, split into appropriate sets with 2 minute rest intervals. The advantage of 8x3 is you can handle a little more weight, the downside is it is more fatiguing and time consuming, and extra fatigue increases likelihood of injury, 5x5 is my main scheme while 8x3 is great for breaking plateau's before going back to 5x5 to continue with the original program.
I have also found that I need to do around 3 or 4 exercises per workout, any less and it isnt fatiguing enough to stimulate growth either. So to summarize I personally have found a workout consisting of 4 exercises, with roughly 25 total reps per exercise split into appropriate set schemes with 2 minute rests to be excellent for building dense muscle.
I have posted a training log called "5 Day Routine" if you feel like checking it out, it is my current hypertrophy/ general fitness program that I have seen great gains from, if you solely want hypertrophy you could drop the conditioning days from it. The downside that I have seen to using low rep training for muscle growth is you have to opt for longer workouts, with higher numbers of sets, and recovery is key. If you are not eating enough good food, drinking enough water and getting enough sleep, that higher weight. low rep training will wear you down quickly, in my own experience. You also have to aim to accumulate fatigue through the week rather than throughout the workout, so instead of looking at it as 3 separate workouts, it helps to look at it as each week is a little mini-cycle and rather than pacing yourself through the workout, pace yourself through the week. Do enough work to make your muscles tired, but do not get them so tired that they are open to injury or become painful. And the key is that your
muscles get tired, if you are becoming tired mentally or physically then your program is too draining. You can learn to feel the subtle differences of how the muscles feel if you practice good posture and focus on the sensation in the muscle, fatigue is a subtle feeling and to use heavier weight/ low reps for muscle growth you have to learn to pay close attention to what your body is telling you and train appropriately, once you get a feel for what your body needs it is just a matter of sticking to the program while making temporary changes as time dictates