For the most part I don't get PIP in any sites, but for some unknown reason, sometimes you just get a nasty PIP in a common injection site. For me when this happens in VG it can be rough for a few days to a week. Walking like an old man with a hip replacement.
calves and quads if you dont hit the right spot.
I was in the hospital some many years ago, before they put in those heparin locks or whatever they are called. I was on pain injections and my butt was sore on both sides from so many shots so the nurse jabs the thing in my quad... hurt for a dang month.
Lots of nerves in both locations, so be careful.
Man I can hit almost anywhere, but I still hate quad injections and they do hinder when I do squats. I have been hitting them for years, but still least favorite even though it is a large muscle and even with a 1" pin.
I think than any injection site could be painful and could hinder train intensity. It depends on the correctness of injection (choosing right point, avoiding veins), purity of material and so on. And of course some preps could be more painful tham others, especially oils.