Mass Gain Guide There are several keys to maximizing muscle growth while minimizing the time spent in the gym. The first one is sometimes under rated in importance, we tend to think, if a little works well a lot will work even better. This is not true with bodybuilding. If you tear your muscle fiber down and don't give it enough time to rebuild, your muscle building results will be greatly diminished. This problem, also known as over training, has significantly decreased results and caused many an injury for strength trainers. We now know that a Build Muscle Fast should only be worked to failure once a week.