@Peter you are correct, I’m not employed as a scientist doing research. I studied biochemistry and physiology as an undergrad and have continued my education on my own, but can tell you for a certainty the podcasts are assigned for high school, college, and masters/phd education. I agree completely that peer reviewed science isn’t bulletproof, as the scrutiny of peers after publication is the real peer review. My ability to validly critique the literature comes from a somewhat rare but definitely not unique position of being a scientist by training, but coach as well. Researchers are indeed mindful of their reputations, but some are blind to what effective training is. Ivory tower syndrome.
My critique of the Ronnestad 2020 paper comes from the interval comparison where 4x5min at about tempo/sweetspot/ftp (depending on the athlete) is not enough to qualify as vo2max training, and definitely insufficient to even qualify as effective FTP intervals. @iMatt66 does a good job summarizing the salient points, and I’ll add one more he missed, which is that higher power intervals will use and train larger motor units as well. So overall, what Ronnestad did was put Thor Bjornsson in a wrestling match against a crash test dummy, whether he knew it or not.
Overall, yes, the 30/15s group did increase vo2max. But let’s also put a short term improvement in vo2max in context of the preceding 5 podcasts, where we show there are different mechanisms of improvement in the short, medium, and long term. My interval suggestions are entirely focused on the long term. One of the FTP training studies we used showed an increase in vo2max from FTP intervals. That would be a short/medium term adaptation that obviously does not last forever. Exploring what’s “under the hood” of a measurement like vo2 is the point of the last five episodes. It’s something that most exercise physiologists (except a few of the modern day greats like Montero and Lundby) don’t try to do in their studies. It’s like saying “this car has X more horsepower”, we don’t know if it got forced induction, maybe it revs higher, did it get a cat delete, more cam lift, electric motors, who knows.