Hi! How are you? I recently signed up to run a marathon; I'm so excited!
That sounds pretty tiring but exciting!
Right?! It's going to be in Boston, next April. I've been training for ages.
Oh is it? That's cool, I'm nowhere near there though.
Are there any big marathons near where you are? 
Not that I know of, I'm not very into them.
Oh no! I love them, they're such a rewarding challenge. The fact that people can run just over 42 kilometres in one go just baffles me, still. 
There's no way i could run one, so I agree!
The history of the event is pretty cool too -- apparently people have been doing marathons since the late 1800s, believe it or not
Wow really for that long? That's pretty nuts.