I can totally relate with you, Emily. Running has changed my life too. I was a fast runner from my childhood but with time I got slow, I didn't know back then. Once in the trials in our school, I participated, thinking that I used to be a fast runner, just to know that "No, I am not." I gave 16 seconds for a 100m run. I don't need to say more about that run. That humiliating defeat made me take my running seriously and within a year of practice, I pulled my timing from 16 to 12.5 seconds. After getting into sprinting I also started taking my physique and health seriously too. And that's how I got into sprinting or for a broader field running.
Personally, I don't like long-running much, I guess mostly because I love high intensity, the same goes with my workouts too.
Ahh, that was too long for a comment but I couldn't resist myself after reading your piece. I haven't written anything about running on Medium yet. I guess I'll come back here again to get some insights from my life, haha.
Coming to your piece, loved it. A lot of information provided in a very concise form. Especially, the sleep. People with their busy schedules often neglect sleep and face shit ton health and mental problems. Sleep needs to be given the importance it deserves.