treadmill trips breaker?

i got free treadmill to day it was struck by lighting so when i plug it in it trips the breaker what component could be doing this ive been reading online and my first guess is maybe the transformer but im not sure really it would be pretty easy to replace and cheap but if thats not it what could be causing it thanks

Pull it open, if it’s not the transformer (your first guess is likely correct, the primary winding’s probably shorted), then it’s probably a blown capacitor or large diode. Shouldn’t be much to replace.