I agree with wigwam here. Sporty is whatever you want it to be. A while ago I suggested the new Nissan micra as a possible choice for my mam and she said it looked too sporty. To me, sporty and Nissan micra don’t really go together but if that’s your opinion then nobody else can really argue with it.
Personally, I think sporty leans more towards looks than speed. Cars can look sporty standing still. Aggressive styling and big alloys are things I’d look for when describing a car as sporty