At one exercise per muscle group you reduce the chances of overtraining.Yes, it is still possible to overtrain on this kind of workout but when compared to
a regular split routine, where you do multiple exercises for a single muscle group in one training session, super sets, drop sets, rest pause sets etc. the chances of overtraining are smaller.
In addition to recruiting more muscle fibers, multi-joint moves help increase the production of anabolic hormones, so if you want to build some serious mass, forget about the
splits that have you training legs one day a week and add more of these into your
regular routine.