Which phrase in the letter is a parenthetical element that lacks punctuation?

Dear Valerie,
How are you? Last evening I was at the marathon. I was surprised to see the number of runners. Even my teacher Mr. Gilbert was running. I #1 ( really enjoyed the run, ) although it was tiring. Thanks for #2 ( training me ) so well. I didn’t win, though. Two kids from my school #3 ( Jamie Lynn and Brendan John ) were the winners. They received gold medals.
See you soon,
Marshall

1. enjoyed the run,
2. training me
3. Jamie Lynn and Brendan John