My name isXXXXX helped you on your last PT question you had. I am a CSCS and MS in EP and have thousands of hours working with with Division 1 college, Division 3 college and professional sports in a strength and condition and rehab environment.
Unless you are working toward a degree in something around human or exercise physiology you can eliminate the NSCA, they require college coursework.
NASM is actually a really good certification to have - they focus on cycling skills training(balance, proprioception) and regular basics and fundamentals to keep things fresh. One of the best, XXXXX XXXXX rounded PTs I had the priviledge of working with was NASM. Now this obviously was a product of his initiative but the certification helped to round him out.
ISSA - is like I mentioned somewhat "ok" but I have seen way too many times, to be frank, complete idiots who have their ISSA - these guys truly are a joke to the trade. Obviously you could use this as a "foot in the door" cert, but you may get grouped with the "idiots" and the stigma that follows them.
ACE - Is decent, not awesome.
To be honest, I would either take the NSCA if you are in school for physio/kinesio or stick with NASM. The NASM program is solid and actually has a great rep. This is coming from a NSCA, CSCS where the CSCS crowd has a tendency to "look down" on a lot (just being honest here
), If didn't have my CSCS and needed PT, I Would do the CPT from NSCA, or NASM if I was not in school. http://nasm.org/