This is somewhat of an elementary concept to bodybuilding and/or building muscle mass, albeit a lot of inexperienced and experienced weight lifters still commonly make this simple mistake. One must remember the basic science behind gaining muscle mass, and that is: Your muscles grow while you're resting, not when you're constantly working them to death. True, they often swell while working out and many gym folks call it "getting pumped," but that is just from the temporary surge of excess blood that pumps into your muscles from the current exertion that is taking place.
Anyway, it is often hard for the eager ones and bodybuilding beginners, along with the muscle-bound fanatics, to not overtrain, at times. I refer to it as "overtraining" when you work your body so hard, that it barely has time to recover in between workouts. When this happens, it is usually all your body can do, in its limited amount of rest time, to repair enough muscle tissue/fibers in between workout sessions - just to get back to its prior state without any gains whatsoever. Now, doesn't that sound counter-productive and like a big waste of time and effort or what???
Take some breaks, don't overtrain your muscles and create some damn time gaps, it is simple as that, when it comes to gaining that muscular mass! In fact, after going through a regular routine of physical fitness training for a couple months or three, it is also good to take an entire week or two off. Remember what I said in my "muscle memory" post? If you've read that particular blog entry, you'll not be alarmed or fear the possibility of muscle loss during your down times, layoffs, off weeks, etc. Once again, your muscles grow during the recovery process, provided that you ingest an ample supply of nutrients, protein, and so on.
Another thing that semi-relates to this "muscle growth" stuff, is to shock your system from time to time. It is a training method that involves an ever-changing routine. If you apply this method, you would completely alter your workouts from month to month with a completely different set of exercises and/or angles of motion. Although, you don't necessarily have to entirely omit certain exercises that focus on the target areas within your desired goals of gain, but I'm just saying: when you shock your body with variety and unpredictable motions, you are apt for a full spectrum of muscle gains along with versatility and flexibility.
I know that there are many professional bodybuilders who eliminate the possibility of this "don't overtrain the muscles" dilemma - so they can gain more mass, by simply working one or two muscle groups once a week. Their routine usually consists of a 6-day-a-week program, with one day of rest, but during those 6 days, they never work or focus on the same group of muscles more than once a week. However, for most people who are not "professional bodybuilders," you will not need to resort to such things. For example, you may be a guy who just wants muscular arms and a toned chest. If that's the case, you could easily have great gains by working those areas hard, about once every 5 to 7 days and ever so often, take a couple weeks off.
Look at it this way: You're just not designed to be a workhorse, and to naturally gain muscle mass without drugs or growth hormones, it will take a lot of time and effort.....
---End of Post 'Gain Mass - Don't Overtrain your Muscles!'