Carpinelli is the go-to guy for references promoting single set protocols. He has published a large number of papers critiquing other people’s conclusions in the S&C field. But I haven’t found many studies that he himself has conducted on strength training protocols, especially when it comes to single vs multiple sets. Not quite sure what to make of that…
Recently, I listened to a round table discussion on strength and hypertrophy involving Brad Schoenfeld and James Fisher, hosted by Discover Strength. James Fisher has long been in the “single set” camp. But in this discussion, which I think is worth listening to, Fisher conceded that there is likely a volume effect. (Apparently this earned him some hecking from a few die hard HIT folks in the audience?)
Part of his rationale was kind of interesting: If there truly is no difference between single and multiple sets, then by random chance, some studies should show that a single set is superior, some studies would find no differencs, and some studies would find multiple sets superior. But, according to Fisher, the studies typicallt show either no difference or some benefit to multiple sets. Ergo… it is likely there is a volume effect, albeit small, and perhaps difficult to quantify.
Personally, this question is starting to feel a bit like beating a dead horse, just keeping alive an argument that Arthur Jones had with the rest of the training community a very long time ago.
The HIT argument has always been a single set, if done right (to “true failure”), is all you need. But then you get into the weeds and ask: what is true failure, how do you know that set was intense enough, or that it was done right? And if that set wasn’t intense enough, then you must have left something on the table, and therefore another set should be of value. And maybe not everyone can get to the intensity level required, or not everyone responds to intensity and volume in the same way, or can sustain the requisite intensity level over a training career. The whole idea that there has to be a narrowly defined optimal stimulus that works for everyone might be a faulty starting assumption.