Probably an inch.
Really? It is quite a lot. I don't know what your arms measure, it's not that important, but could you take your cold measurement and then pump up both the bis and tris to the max and measure again? If you're natural it probably lessens the pump effect but you should still get plenty of blood there. You don't have to say how big your arms are just the differential. I would be really interested if a few solid guys here did the same. I used to think I probably got an inch, but when I actually tried it was like maybe 1cm. Furthermore I think you actually might get a bigger differential the next 48 hours after a murderous arm workout as some inflammation and water buildup sets in. Those all day long arm sessions a la Piana only appeared to work due to local inflammation. Come on guys, do it for me, for research purposes
As a sort of related matter, I've been playing in my head with perhaps shooting some base hormones (just the base hormone without the ester which has to be cleaved before the hormone does its thing) suspended in MCT oil. Maybe there could be some longer term local hypertrophy? Some say just putting a small amount of MCT oil itself, or just any fatty acid, in the muscle say after a workout for that specific muscle, in itself stimulates a small hypertrophic response, and medium chain triglycerides (think the fatty acids in coconut oil for example) have been shown to activate the androgen receptor all by itself. There was some study showing chickens, I think, injected with nandrolone in the chest caused an outsized hypertrophic response in the chest in particular. All this is highly
theoretical. For reasons my arms are absolutely pathetic right now, haven't trained them for years but I just now started hitting them twice a week and hoping they respond. I actually have loose skin hanging off my tricep.
So I was playing in my head with ways to get even better results, even if they will necessarily be small (with local site injects I mean). Only problem is how to source base hormones. One thing I can get is suspened methyltrienolone which is shit strong even in microgram amounts while being extremely liver toxic but I was thinking maybe 25-50mcg injected in the arms instead of the 1 or more milligrams usually ran as short cycle bursts. As extra info, a number of years ago the whole Greek weightlifting team was suspened over methyltrienolone, I think they figured the doses are so small it should clear faster that other AAS but the tests are super sensitive nowadays. Other considerations would be trestolone base, which is also active in microgram/day amounts, stanozolol, test base, tren base, Dianabol and etc. Other considerations would be IGF-1 DES which some claim is somewhat effective as a local enhancement vs the more common LR3 which is systemic and longer acting. I was further thinking of perhaps some Fiasp insulin which is active within seconds, regular GH and etc, hit your arms with injects at the end of your regular arm workout, trap the peptides and blood in your arms for longer with those Kaatsu bands and do the Kaatsu protocol hoping to get a longer stimulus which otherwise would disperse into systemic circulation within minutes.
BTW, has anyone here played with the Kaatsu bands at all. They will cause one hell of a pumped feeling if nothing else. One mechanism behind why it works in studies is local hormone induction like IGF-1 and other beneficial metabolite accumulation.
Another long ass post which hardly anyone will read but perhaps some rare individual here might find mildly interesting