I would say this, and it is more of a general point, but it applies here: Email is dead.
So if you are an HSer who is email blasting coaches with your times, chances are, they aren't going to see them. On my highly curated work account, I still get close to 200 emails a day. Emails are soft touches. You have to get a hard touch somehow. A phone call, a face-to-face visit, something. In college at a D2, I connected with some guys on the team and used that to get a face-to-face meeting with the coach.
When I coached, if a kid wanted to run in college, I would run them in a marquee event where I knew college coaches would look at the results and let them know that this was their chance to make their mark. If there were a program they wanted to hear from, I would contact the coach on their behalf.