If you hire a running coach, your coach is going to design a program that is going to actually test you physically and mentally, and push you to your physiologic limits on a regular basis to make you stronger. 

Any running coach will give you a series of workouts to execute. 

And when you do runs correctly then what happens is that you do the maximum amount of tissue damage that your body can sustain and rebuild before your next workout.

Today on the Doc On The Run Podcast we're talking about why runners need to flirt with overtraining injury.