I don't fully get the "lowers blood pressure" claim. Doesn't Table S2 in the paper say that blood pressure stayed roughly the same for people doing high-resistance IMST and went up for the control/sham group doing low-resistance IMST? The question in my mind is "why does low-resistance IMST increase blood pressure?" Am I missing something?
Casual vs ambulatory blood pressure readings seem to account for the difference between what is reported in Table S2 and what is shown in the main paper. I don't know which kind of reading is more clinically significant or reliable. A little worrying that its not seen in the ambulatory too.
Comparing group means might not be quite so informative in any case, because of baseline effects (e.g. you'd want to do paired tests I think to compare the diffs)
By my understanding "casual blood pressure" is when you sit for 5 minutes in a doctor's office then have a blood pressure measurement taken [1]. "Ambulatory blood pressure" is when a monitor is strapped onto you and automatic readings are taken periodically (typically half hourly) over a period of time (typically 24 hours) then averaged.
There is some debate (according to Google), but diagnosis of hypertension typically involves an ambulatory measurement over a casual measurement. It strikes me that the ambulatory measurement is the more important one from a long term health perspective, and it's odd that the paper chose not to mention the ambulatory measurement along with the casual measurement, though I'm not a medico.
As an aside, at one point I added a microcontroller to a cheap Aldi blood pressure monitor to do ambulatory measurements. A doctor seemed keen to diagnose hypertension based on a few casual readings, but I was keen to base the diagnosis on more data.
