Periodization: If a trainer or athletic coach does not know what periodization Accomplishes or who does not know who Tudor Bompa Phd is ............. RUN!!!! Why??? It takes about 6-10 weeks for each major body group to get into a fitness mode A It is smarter to work groups of muscles B It is very hard to isolate a muscle that produces a complex movement Due to these two competing A versus B any plan to get fitter or healthier actually integrates and alternates between group work and isolation work. The trainer is supposed to design this and pace you so you will not injure yourself!!! Even if the trainer did not screen you first a comptent trainer should know if you got a weak side( for instance) and proceed accordingly. I always have the weaker side go first and do a forced rep .partial rep/ rest pause to get the stubborn side to catch up. If these terms sound weird see Weider Principles . A well designed Peri