there may be different organizations with their own standards but the one I looked at has no pre-requisites at all. Here is what they say:
“BeyondBarre Basics training has no pre-requisite required; each level thereafter requires a pass and BB certificate of completion of the preceding level of competence.”
Frankly, I find that extremely disappointing. I believe the every fitness instructor should have a personal trainer or group fitness certification which requires CPR and CEUs but if there is money to be made of the latest fitness trend, then some organizations may not want to trifle with those details.