Swimming right into animal, getting hit (12)
I believe the answer is:
breaststroke
'swimming' is the definition.
(thesaurus)
'right into animal getting hit' is the wordplay.
'right' becomes 'R' (common abbreviation).
'into' indicates putting letters inside.
'animal getting' becomes 'beast' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'hit' becomes 'stroke' (stroke can mean a hit or blow).
'r' placed within 'beast' is 'breast'.
'breast'+'stroke'='BREASTSTROKE'
(Other definitions for breaststroke that I've seen before include "What swimmers may do" , "Adam Peaty's swimming style" , "Natant style" .)