Hello flex, yes it's definitely a interesting debate and I'm sure it will never truly be answered.
The difficulty with scientific publications is that, the populous used have great hetergenatity - being the participants varying substantially (ie body types, genetic makeup, training history) and dissemination of the findings hard to interpret. In short, there are too many variables that cannot be controlled.
We do genotyping, we look at what genes or markers patients posses in terms of how well muscles can be trained and principally how hard and what recovery is need to optimise recovery, and in turn we can predict which patient might benefit different rehab programmes, higher and lower intensity programmes respectively. I know this is a different angle but there seems to be good theory behind it. Genetic disposition is a contributing factor to recovery and is a factor for optimal hypertrophy.
I do believe training 70-80% of 1RM is the best for hypertrophy, but as discussed very much determined by the individual in question. In addition, using extended eccentric times are important, providing neccassry sheer forces (tension) to replicate micro muscle damage. For example ..... 3/4 seconds lowering, 1 sec hold, 2 sec concentric pushing the weight up with a 1 sec hold in each lowering and lifting phase in that repetition. Though again, training experience also effects percentages recommended for functional and maximum hypertrophy zones. There are so many area to discuss.
I ask a question? Does it really matter when taking AAS that we use the same hypertrophy training zones ie 70-80%? I'm sure a large number of members do take them, so only natural non users or in-between cycles this maybe applicable. My reasoning for this is that, with AAS the substantial gains in strength provides adequate overload and progression of weight being used, consequently muscle adaptations occur. As well as the other advantages of AAS in protein utilisation.
Would be nice to hear anyone else's thoughts....!!