Volume and Intensity Cycles
One of the easiest ways to royally fuck up a program aimed at long term progress is to not take into account the role volume and intensity play when designing it.
You dont have to look far to see a high intensity/very low volume trainee make nice gains for a few weeks, and then peter out shortly after those gains are made.
There are several different reasons for this, but to keep things simple, we will keep intensity as a word used to describe the training method targeting the central nervous system as a PRIMARY. This is a VERY important aspect of training, but once those short term adaptations have been made that tend to come fairly quickly, gains tend to slow down massively without introducing a new stimulus.
You also dont have to look far to find athletes using a high volume/low intensity approach, that tend to make their gains a little more slowly, but start to run into lack of progress in strength gains, overuse issues, pain in the tendons/ligaments, etc., and tears and or strains, which keep them from staying more consistent with their training. Many of these individuals will initially notice a nice change in physical appearance right off the bat, and then soon after, that comes to a stop as well. Again, to keep things simple, we will keep volume as a method used to PRIMARILY target hypertrophy.
The reason neither method works in the absence of the other is simple. The central nervous can only get SO efficient, with a given amount of muscle tissue at performing a given task. At that point you can either a. give it a different task to adapt to (change exercises, etc.) or you can add some more muscle for it recruit in the same tasks.
On the other side of the coin, a solid progression of load is not optimal with a high volume and low intensity approach for the entire training cycle. Raising the intensity for a while, then shifting the focus to hypertrophy can work wonders here, as you now have a more efficient central nervous system, much of the tissue has time to recover, and you can progress the LOAD with the hypertrophy specific work. These two methods compliment each other very nicely when used correctly.
Now before it comes up that "omg everything is neural and low intensity work affects the cns too!", WE KNOW. We also know that high intensity low volume work affects hypertrophy. Go to the disclaimer and read "PRIMARILY", as in , the main focus, and the method that MOST affects each aspect.
So to make it short and sweet, both volume and intensity MUST be factored in, but NOT in the same session, ESPECIALLY when speaking of athletes in training for sporting endeavors other than weightlifting/powerlifting. It can be done in different training cycles, different workouts within the same micro cycle, etc., as long as they are both factored in, given adequate attention, and allowed adequate time to recover.
If youre looking at your program, and trying to figure out why you have stalled, or are going backwards, figure out which quality you are focusing on, and how often. Using two higher intensity workouts to one hypertrophy focused session works EXTREMELY WELL in my experience, with the hypertrophy session last in the week and one or two more rest days following that session. Lots of coaches program specific phases lasting months at a time on one quality or the other, this also works. If youre only doing what you feel like doing THAT day, and not factoring in the other sessions you will be performing later on, its a quick road to nowhere. Think about the big picture at the end of the road.