if i were doing an exercise for 12 reps every 3 days and wanted to increase the intensity, which should be the method?
>shorten the interval down to every 2 days
or
>increase the reps to 20 every 3 days
(assuming i cant switch to heavier weights)

ive been hitting the weights for 2 weeks now, a pair of 6kg (~13 lbs) dumbbells.