Total body or total body workouts are a personal favorite of mine and they give me excellent results. The main advantage of a full body workout routine is the time you save. Working all muscles in the body on a single day means that you don't have to be in the gym as frequently. As a matter of fact, I am in the gym just 3 days per week. However, the workouts tend to be lengthy and especially demanding.
For beginners, a complete body workout routine is the best way to pack on muscle very quickly. Stimulating all the muscles in the body at once tends to trigger growth provided your nutrition is in order. Just make sure that the workout routine is a tried and tested one that is both balanced and not overly taxing.
So the cons of the whole body routine are that the workouts are lengthy, tiring and physically demanding. Also, if you have any weaknesses, it is difficult to focus on individual muscle groups and full body workouts are often dominated by compound exercises. While they are more favourable for overall development, some weak parts could potentially be neglected.
The split day routine is the professional body builder's favorite. Some of you may make an erroneous connection and assume that since bodybuilders have a huge amount of mass, split routines are excellent. Not quite. Bodybuilders always lay the foundation with a total body routine and then begin to focus on bringing out certain areas with split routines.
This is the greatest advantage of a split routine. It means if you have any weaknesses i. e. small chest/small legs, you can bump up the work rate on those particular parts to bring them out a little more. It would be difficult to do this with a whole body routine as the exhaustion would dampen your performance when working on other body parts however, since you are only working on two muscle groups with the split routine, upping the ante carries less detrimental consequences.
All in all split routine workouts give you more freedom and more control over your workout but they are more prone to bias. Many bodybuilders hate training legs and it comes as no surprise that most of them find excuses not to go to the gym when they are meant to train legs. Just don't fall into this trap.