That might be a bated question, asked by Mr Z, to see how many would fall for it. Or maybe Mr Z is that confused by the basics of training. Or maybe a combo of both, who really knows. See not too many jumped to answer that since 12-19-13 and Mr Z appears to have vanished all together.
As far as reps go:
20 reps can do for you what 5 reps can't. And 5 reps can do for you what 20 reps can't. In other word, you have to experiment with reps and sets to find what will give your the best results in the shortest amount of time. 20 reps can build muscle mass, as well as 5 reps, just have to spend a little time to find what works for your individual body type.
Try not being influenced by Mr Big Balls of 2013 (or any other "champ"), and what he may suggest or do in any of his video's. Or the gym "expert" who seems to know all the answers. Also including me (no expert by any means) or any one else on GB. Take any advise, or new idea, and approach with caution at first. Try a new program for a good 6 to 7 weeks, the first 2 weeks are more of a breaking in period, getting accustomed to the change in exercise style, etc. If results seem good, than you get an idea of how your body responds to that type of workout. If no, or poor, results...than try something different.
Going to failure, for a BB'er, is really never needed. And may even halt progress for some. If wishing to try experimenting with that, and other different methods, that help yourself. You will only find out the results by doing it on yourself.
K.I.S.S. (Keep It Simple Stupid) might be a good motto to keep in mind when planning any future workout. I know I do. Good Luck
Good advice. I also try to keep a consistent training and diet regimen
for 6-7 weeks. Then I reassess, and try to change the regimen minimally. The point is how do you know what works, except by experimentation and consistency? I am no expert by any means as well. I throw out my theories for constructive feedback, and to share what has and has not worked for me over the years.
For reps, here is an example I like to use....
3 sets of incline dumbell press...
75 lb x 10 reps
80 lb x 8 reps
85 lb x 6 reps
Once I can perform this weight/rep scheme, the next time I perform this, I work for:
75 lb x 12 reps
80 lb x 10 reps
85 lb x 8 reps
Once I can perform this scheme, I move up the dumbells in 5 lb increments and go back to the 10, 8 ,6 rep scheme. If I feel I can
surpass the second scenario, I slow the reps down. This way, I am
steadily increasing the load I am lifting.