An e-mail example.

Dear Jami,
It might be surprising for you that I decided to join the New York marathon this year. I will go to New York close to the race. It would be wonderful to meet you in Connecticut after the race.
The race is going to take place 6 months later from now. I made my training plan for the race the other day. Let me introduce to you my plan for the race.
I am going to run 2-4 days in a week up until three weeks beforehand. After that, I will try a half marathon (20-km) at my own pace. Then, I will focus on stretching and walking to recover my body for three days.
Two weeks before the race, I will to try 10-km run at faster pace. And then, I will reduce my training time around 70-80%.
One week before the race, I am going to reduce the time of running until 50-70% to get rid of fatigue in my body. I am going to take total day off before the race day.
This is my training plan for attending New York Marathon. If you have any advice, please let me know. I am looking forward to meeting you after the race.

Cheers,
Aka