AFFA is a good one too
It really doesn't matter....your either a good salesman or your not.
You could get the best cert out there but if you suck at being a people person and a salesman your doomed regardless of what cert you get.
http://www.afaa.com/
Sales doesn't factor in if you work for a company, it's just about you training clients.
If you work for yourself, that's a whole different ball of wax.
The overhead of having your own gym, insurance, and having to sell people just isn't really me.
I'd rather work for a high end gym or for specialized clientele.
I don't need the hassle...
DIV