Specific training has to do with the time that is taken between the training of a specified body part say the quadriceps. The best thing to do in regard to specific training is to ensure that you give the individual muscle groups enough time to recuperate and by extension the whole body. For systematic resting it has to do with letting the body rest adequately by not training it on consecutive days. An effective way to adopt systematic relaxation is to train on two consecutive days and letting the body relax on the third. Make sure that each body muscle is trained every five to seven days.
lean muscle x