Quote[/b] ]From what other research there is on the time course of genetic expression in response to overload, it is clear that we don’t even come close the amount of time needed to elicit the greatest hypertrophic effect. But what are you going to do? We have to lift the weight and lower it over and over in order to overload the muscle. From the overload research, I personally feel longer time under tension is better. But you have to balance that with CNS fatigue, and absolute load.
More sets with heavier weight is better than fewer sets with less weight. But there is a limit to our exercise tolerance. So you have to figure out a way to get as much loading of the muscle as you can, as often as you can, and still be able to constantly increase the load over time, without burning out or getting injured.
Keep in mind that HST does not dictate that the total volume (i.e. number of sets per body part) over the course of the week should be lower than what a person is accustomed to using with traditional routines. HST only advises that the volume be evenly distributed over more workouts in the same time period. So if you are used to doing 9 sets for back on "back day" using a traditional routine (e.g. training each body part once per week), HST would have you do 3 sets at a time for 3 different workouts.
Obviously, a guy who is used to doing something like 12 sets for back once per week, is not going to gain much by dropping to doing only 1 set for back even if it is 3 times per week. He went from 12 sets to 3 sets per week. Not only that, but HST would have him use submax weights most of the time where he is obviously plateaued and used to doing 100% max weights (Not true 100%, but 100% with the fatigue that inevitably accumulates by the 3rd set). This is just too great a reduction in training to provide him with significant gains. The key here of course is Strategic Deconditioning, that would then allow him to begin growing again, with less "average" weight and volume, but higher frequency.
Well, for me, 2 sets is enough on most bopdyparts. But then again, with body parts like back, I will usually do 3 sets at different angles of pull and grip widths.
But the amount of volume each person is used to varies. I am not saying that you have to train to your volume limit. I'm just saying that if 1 set isn't enough, do another. Do too much and you'll begin to get progressively weaker, and/or injured and you will lose your desire to train.
At first, you won't know how much is too much and how much is too little. So, start with 1 work set per body part per exercise, and work up from there.