I’ve been pondering this for a few days, did some reading and have come to the conclusion there is little quality evidence to support anything but basic standard sets. So much of the following is based upon research – but my interpretation of it to fill in the holes and some discussion at work with the S&C experts.
There are a few set styles – I’ll use the terminology I’ve learnt not the broscience terms;
Changes in intensity;
Constant load / constant rep – ie 3x10@100kg
Increasing load /constant rep – ie 1x10@100kg, 1x10@110kg, 1x10@120kg
Decreasing load /constant rep – ie 1x10@120kg, 1x10@110kg, 1x10@100kg
Changes in reps;
Constant load / increasing reps – ie 1x6@100kg, 1x8@100kg, 1x10@100kg
Constant load / decreasing reps – ie 1x10@100kg, 1x8@100kg, 1x6@100kg
Or a comination of the above;
Increasing load / decreasing reps – ie 1x10@100, 1x8@110, 1x6@120
Decreasing load / increasing reps – ie 1x6@120kg, 1x8@110kg, 1x10@100kg
Some of the above approaches do target specific adaptations – specifically in very broad terms either hypertrophy (from a body building approach) to strength/power (from a sports performance approach). And a few of the above are a plain stupid approach (you'll be able to work out which ones based on what you have summarised in your previous post), although you see people in gyms doing them.
You are right on the reverse pyramid approach – it accounts for fatigue so more volume can be attained (volume being very important for hypertrophy / body building approach). But from an athlete training perspective it’s perhaps not the best approach. The primary stimulus for pure strength gains is intensity of effort based of %RM (in an unfatigued state!), so as you lower the load to account for fatigue your actually starting to minimize strength adaptation as %RM based of an unfatigued state. This approach does work for body builders, but not as effective for athletes.
I know this seems stupidly simple, but the best approach for athletes is still constant load / constant rep. The argument against this approach is that only the final few reps in each set are actually hard and the rest are a waste of time. But that’s why athletes generally (depending on current periodization) train with lower reps. So in a 4-6 rep range they are absolutely maximising tension/%RM and maximising strength gains.
Another approach I quite like is increasing load /decreasing reps – in the not very well trained this maximises strength, by removing fatigue from the equation, I use this approach with new clients so they get strong fast and keep paying me money. The problem with it long term is it burns people out and does not have the same volume as other forms of training – hence for general clients it may limit hypertrophy if all other factors are there (diet, no concurrent training, steroids…). Generally I’ll only take this approach for 4-6 weeks – no evidence for that, just seems to work.
So in conclusion,
Certain set approaches do favor certain adaptations (and some formats are a waste of time).
Constant load/rep sets are still the best for strength/performance – particularly if the rep range is kept in the lower ranges.
Drops sets are only good as a body building approach, for athletic performance not a great approach (even for endurance sports).
While a drop set will certainly maximise type IIA’s &IIB’s (great hypertrophy stimulus), via fatiguing effect – but this approach limits the neural side of adaptation – specifically twitch summation for maximum strength.
Henneman's size principle dictates that slow twitch fibers are always going to be fully active when type IIA’s &IIB’s kick in. So anything in the higher intensity ranges of %RM will be fully stimulating them.
For pure muscular endurance I’d still not use a drop set, I’d just go all out and do big reps – 25+ minimum. To stimulate slow twitch fibres in this sense you need a strong metabolic stimulus – but I still think this can only be achieved ‘effectively’ by aerobic activities as the primary slow twitch adaptation is always going to be increase in profileration and size of mitochondria and vascular neogenesis.
