For weight training, without steroids, 1/2 lb.-1 lb. per week is normal. However, as with any type of training, you will see plateaus in weight gain. This can be attributed to over training or an indicator that you need to switch up your workout routine. You will also see plateaus because of your body's need to be in a homeostatic state. When you gain weight, or lose weight, your body tries to equalize itself because it thinks that something is wrong. The key is to not get frustrated, continue with good eating habits, and to allow yourself time for recovery. Hopefully this helps.