Over-training occurs when you train your body beyond its ability to recover (its so-called recovery-ability). If your body cannot recover from the last workout then it will be unable to adapt and unable to grow. Symptoms of overtraining include: (i) A higher-than-normal resting pulse (ii) Illnesses become more frequent and last longer than usual (iii) Muscle spasms while resting e.g. eyelid twitch etc. (iv) Shaky hands (v) Loss of Sleep (vi) Loss of appetite (vii) Unexpected and unexplained fatigue (viii) Unintended weight loss and MOST IMPORTANT OF ALL -- (ix) very slow or non-existent gains in exercise poundages in the gym; i.e. static poundages or poundages that are only a few pounds more than you were using months ago. In extreme cases, overtraining can lead to a loss of strength and the use of reduced poundages. Solution: If you are overtraining on your current routine, then cut back on workout-days per week, and exercises and number of sets used. Best of all give "The Hardgainer Method" a shot for 6-8 weeks just to see what you are missing. In most cases the person who tries this for the first time will experience a rapid gain in strength and muscle mass, along with an increase in energy.