Sounds like a half-marathon is a piece of cake for you! I 服了 U啦！
No real bricks from me. Good writing! Just some of my thoughts:
Looking back, I would do better if I had more training, espcially hill training. -->I would have done better, I could have done better.
there are a lot of hills or up and down along the way-->maybe: there are a lot of uphill and downhill running, or the trail is very hilly.
I would have not signed up for this event if four of my colleagues had not signed up for the event.
To make a "good" writing "great", I think you would need to rearrange of your sentence order a little bit to have a better flow. For example:these two sentences:
I followed the 1:50 pace leader for first half of the course. later you said:
I was ahead of the 2 hour pace leader all the way and sprinted for the last 0.1 miles.
It wasn't very clear to me which pace leader you followed for the second half of the course. You left me wondering about that. Also, is there a 1:55 pace leader? It feels like you finished between 1:50 and 2:00.You mentioned this:
My primary target was to break my 1:50 PR (personal record, December 2010), and if not, the backup target was 2 hours.
but you didn't follow up on this later in the article. So I am not clear whether you reached your primary target or not. or maybe you did it intentionally, you wanted to keep your time as a secret. :)
And I think the one who cursed you is beautifulwind. haha.
