Hi there the 15 – 20 reps are for the injured side and the 6 – 10 are
for the uninjured side, so for example if you are doing a DB bench press
and your left shoulder is a problem you may do 4 x 15 – 20 @ 25kg on the
left side and 4 x 6 – 10 @40kg on the Right side, cheers, ash