The only one I have heard of is below. I have been looking into this as well and found that all the Road Runner across American certifications fill up fast….
Credentials matter so why not go with the best?
The USATF has great certifications if you are looking to work with top tier athletes. They offer a great two-day workshop on weekends nation wide. I highly recommend the level 1 cert. and from there you can advance to level 2 etc.
Here is the link: