Overtraining

When you are weight training heavily to gain weight, the exercise puts a strain on your body, so make sure that you get adequate rest and recuperation after each of your workouts. If you over train you are not giving your muscles enough time to repair which will impede the effectiveness of you next workout. If you are not at maximum strength you won't reach your muscular potential. You could also injure yourself. Make sure that you approach your weight gain and your muscle gain in a paced and balanced approach.