Are there advantages to breaking up a workout?

Question

For instance, say you're doing an HST (Hypertrophy-Specific Training) routine, and you can choose between Routine 1 ad Routine 2. In Routine 1 you would be doing 3 full-body sessions per week, and in Routine 2 you would be doing 6 upper and lower body sessions per week. Assuming that each workout is done on a separate day at roughly the same time of day, are there any advantages to one routine over the other?

Routine 1:

S M T W T F S            
  F   F   F      

Routine 2:

S M T W T F S            
  U L U L U L     

Also, I do realize that there may be psychological and time advantages in both routines; however, I am asking strictly from a physiological/physical standpoint.

Answer 1

The first routine is low on overall weekly volume in terms of sessions in the gym and I would recommend if you chose this route to achieve hypertrophy what you understand that as you develop into a intermediate/advanced lifter that the time you spend in the gym during these 3 session will increase to a significant amount. Whole-body programs are designed to maximise neural efficiency more than hypertrophy for the average person and thus incorporates more recovery.

The second routine is a more familiar hypertrophy body split and will allow you to break up your exercises over more days, thus making your sessions shorter than the first routine.

By having more sessions you can spread the volume from the first session over the week eg.:

M       T          W         T                 F            S 
Bi+Back Upper Legs Tri+Chest Lower Legs/Glutes Sholders+Abs Rest

It all depends on what your goals are but having a equal distribution of legs to upper body will mean your legs may develop faster overall than what is traditionally an "aesthetic build" (there aren't as many muscles in legs as there are in arms+chest+back+sholders).

Conclusion

Both work well and have their own benefits and issues. It also goes without saying that to progress on either you need good food and sleep. From an efficiency perspective you may meet your goals faster doing the hypertrophy routine but in reality the real winner will be whatever routine has the most overall exercise volume.

The preference is really personal, best not to overthink it (try both for 6 weeks each with linear progression and see what works better!). If you don't want to be at the gym every day but don't mind spending a long time there when you are, go for 1.

If you like being at the gym but cant spend a long time there, go for 2.

Answer 2

Psychological issues aside (as requested), there is the big, BIG issue of physiological restitution.

You've probably heard of the muscle group rest period of 48-hours since both your layouts seem to follow it. But your central nervous system (CNS) is going to be taking a hit 6 days in a row if you follow the second routine.

While your muscles may be getting adequate rest, your CNS might now, and this regimen of overtraining is something that can cause severe and chronic tiredness and exhaustion, even on rest days. People often find it very hard to stick with such routines.

But of course, there are people who do this, with great success. But in order to achieve success with such an overpowering schedule, you need to be extremely vigilant with your diet (getting enough of every macro AND micro nutrient) and your rest (enough hours of sleep every night).

How we deal with it will differ from person to person, but discipline in diet and rest can very well make up for the harsh workouts. But keep in mind, a lot of people will find the combination of that much training, and that much attention to diet and rest, very challenging to keep up in the long run.

Perhaps try it for a few weeks and see if it's for you.

Answer 3

Is 6 days better?

Yes. You can bring more energy to each workout and get the same work done to higher quality which leads to better progress. Also you have more room for variation to keep you progressing.

But you need to lay out the routine correctly. There are no black and white answers. Can you give an example of the routines?

Ideas for setting it up

ULULUL facilitates overloading and high fatigue, is usually more effective as a muscle building approach. However it can be done as a very effective high frequency strength program. You would normally do shorter workouts compared to doing FFF.

F-F-F has extra rest which would benefit a more strength oriented training approach. In general gains would be a tad slower though, three days a week is limiting your potential. As you progress workouts will have to get longer and longer, at one point the quality of work will suffer because the workouts are so long. That's when people are forced to split the work into 4/5/6 days per week.

Generally the sweetspot is 4-5 days a week of training for most people. The extra rest is valuable psychologically.