as of 2015 what is the recognized certification for personal training?
It depends on what kind of education you’re interested in, or the kind of clientele you’re working with. If you’re working with a general population in a fitness club for instance, go for a neutral certification from NASM/ACE; if you’re working with a category of special population (rehab, etc) then look for specialized programs. I know ACE has some such offerings; if you’re interested more towards research, look into ACSM.