lift heavy or lightheavy and light weight traininglift light or heavybenefits of lifting heavy weightscan light weights build muscleshould i lift lighter weightsshould i lift heavy or lightshould i lift heavyhigh rep vs low replow reps vs high repsbest rep rangehigh reps vs heavy weightslifting heavy weightslight or heavy weightslight weights build musclejeremyethierjeremy ethierhigh reps or low reps light