You can scour YouTube for a whole host of videos on racehorse conformation; might be top heavy on yearlings & sales cuz they're probably promotional videos to get people into ownership.
Blood-Horse had a good series on VHS back in the day; maybe they are uploaded somewhere.
Here's a good starter video from probably one of the few who actually knows what they are talking about; covers most of the rudiments in just over a minute, even answers your question about sprinters v. routers:
https://www.youtube.com/watch?v=QMdX...b3JtYXRpb24%3D