Hiya,
It's generally well known that BMI is only a guide and does not apply to people with particularly high muscle percentages, etc. Doctors will use it if it's clear you're not an 'elite' athlete - and if there's any doubt, you can get 'fat tested' - this is an unpleasant and slightly painful experience with calipers!
I'm involved in a sport with quite a few very high level athletes - if we all went away, I'd be the only one not clinically obese!
Just remember, statistics and measurements can be used for all sorts of things, but they usually have a restriction or caveat too.