@Stephen_Judd This is a very interesting observation. Thanks for sharing the link.
It also squares with the cautionary tale shared by @Don_Q earlier in this thread.
FWIW, I have continued to creep slowly upward in my BFR bicep dumbbell curls - now at 16.5 lbs, which represents roughly 50% of my 1RM - and can offer an n=1 on the other end of the same spectrum.
I have suffered no meaningful muscle discomfort/stress following any BFR session… often making me wonder if I’m doing it right
But perhaps this is simply due to my having started out with what apparently was an entirely minimal load (5 lbs against my 1RM of about 30lbs at that time) - using a cautious 30/15/10/10 routine. Although I was doing it twice in a row since it felt so easy.
Then, day by day, I increased the load slightly - and then stopped doing the routine twice (i.e., did it just once).
When I hit 9 lbs, I took that fourth set to 100 reps - still no failure. Next day, 10 lbs taken to 50 reps on final set without failure. From there, as I continued to baby step my way up to my current 16.5 lbs, I’ve simply stopped at 30/15/15/15 (single routine for each arm) on the final 15th rep.
Still haven’t felt any need to stop before the routines are completed - i.e., “no failure.” This may be keeping me from accomplishing something metabolically meaningful? There’s some minimal discomfort from the BFR. But it feels safely uncomfortable, not dangerously uncomfortable.
While so my veins are popping out significantly under BFR (though I’m always pretty vascular), my hands get cold, and I feel an internal “pressure” of some sort, I’m constantly checking the fleshy part of my palm to ensure I’ve got around 2 seconds’ worth of full capillary refresh.
Whether I’m getting any benefits (vis-a-vis traditional bicep curls) remains an open question