There are a lot of new training methods that suggest high rep work (30% one rep upward for 40-50 reps) and plenty of older systems with lower rep work (around 70-80% of 1RM).

 

A study from Oklahoma State University found that there was no difference in strength recovery between the two.

 

They ran 5 sets of 16 reps with 40% of maximum against 5 reps and 8 sets with 80% of maximum.

 

Taken from Journal Strength Conditioning Research, 2015.