However, this question is predicated on a common misconception that high weights = bulking and small weights Mean toning. MYTH, indeed! Dumbbells of varying weights will not tone your arms. Lifting Weights Won't Turn You Into a Monster! The truth is that strength training helps build muscle mass, which in turn boosts your metabolism and helps you lose weight. However, only performing bodybuilding exercises won't help you achieve your goal. You also need to incorporate heavy lifting into your routine for it to have an effect on your arms. So yes, 1.5 kg weights can be used for arm toning.