Gym is present in supported types as mentioned on Google's site.
https://developers.google.com/places/supported_types.
I just can't seem to figure out how to filter specific types to show results.
So far I have tried:
let field = GMSPlaceField(rawValue: UInt(GMSPlaceField.types.rawValue))
autocompleteController.placeFields = field!
let filter = GMSAutocompleteFilter()
filter.type = kGMSPlaceTypeGym
autocompleteController.autocompleteFilter = filter