MUSCLE When you try to maximise muscle mass you should aim for high repetitions. If you stay in a rep range from 8-15 you will build more muscle mass but will therefore not gain as much strength. If it is strength you are aiming for, please read on.
STRENGHT When trying to gain strenght you should stay in a low rep range. Reps from 1-5 are good when your goal is to gain strength and not so much mass.
Remember that it is good to combine those two. To confuse your muscles and to get a good mix of both. Personally I dont think that there is a point in gaining mass and dont have the ability to use it in every day life. Again it depends on you goals.
