This can not be stated enough, Muscles Do Not Grow In The Gym!!! Indeed it is in the gym where they are stimulated into growing if worked enough. However it is infact at home, at work, when resting and when sleeping that the muscles are really growing. Some people dont realise this but when a muscle is trained it is torn down and the result is that there are millions of microscopic tares in the muscle tissue. If it is to grow then these must be mended and the quicker they are mended the quicker the muscle can recover and grow. Of course this is only a very simple picture here but to explain the whole process in scientific terms this whole web site could cover this very large topic. So you go to the gym, you place a stress on the muscle that it hasnt been given before and if you sleep well, providing you follow all of the other Bodybuilding Commandments then there should be absolutely no reason why that muscle wont grow. Your body can only take so much and needs its rest. It is at times of rest that large amounts of hormones are released which help and aid in the repair and increase in muscle mass. It is vital that if you wish to change your body in a short amount a time as possible that you get at least 7-8 hours of good sleep each night. Some people take a small protein shake to bed with them or a light meal replacement and wake up sometime in the night to take this. Remember if sleeping for this amount of time your body is starving itself for this period as well. If you do wake up it would be agood idea to consume a very light shake and back to bed. This will help keep your body in an anabolic or muscle growing state.