The main arguments of adherent of basic exercise is the assertion that compound exercises involve a large number of muscle fibers, thus contributing on increase muscle mass and strength. But in order to grow, the body must receive a constant load. And if for quite a long time to provide the same load, at the end your body will not respond to the training. Besides getting used your mind is overloaded, and this is much worse. You may overtrain or lose interest in training. Generally, performing basic exercises is easy to undermine your energy source, because powerful movement not only involve a lot of muscles, but also require a lot of energy.
Another negative aspect of the basic exercises is high risk to get injury. Exercises must be performed technically correctly. Therefore, beginners should not immediately get involved in this system.
So, you have in the arsenal a huge selection of isolation exercises, that is, those which involve in the work only one muscle group. But movement whiles this workout can be seemed only in one joint. For example, the extension of the legs while sitting in an exercise machine loaded quadriceps, but the motion is seemed in the knee joint; dumbbells fly loads pectoral muscle but motion is seemed in the shoulder joint. It is believed that the isolation exercises are not suitable if you are going to gain some mass, their purpose is form and relief. But if that were the case, it would not be the main exercise in bodybuilders’ workout. This conclusion is important, because many people believe that isolation exercises create only the illusion of exercise and are not suitable for serious training.