Optimal bicep training: How many sets per week do you need?
A recent study investigated this by testing 3 weekly set protocols in trained subjects. Groups preformed either 9,18 or 27 sets of bicep exercises per week for 6 weeks.
What they found was that there was an inverted U response.
The study showed optimal results using 18 sets per week, 9 sets were not enough and 27 appeared to be overtrained by the end of the study. One draw back of this study was that subjects were allowed to continue training outside of the study.
This gives us a bit more information on a possible guideline on what might be appropriate volume for biceps training. That being said the data also suggests that some subjects respond better at the extreme ends of the spectrum.