Just a couple more points--
1. I believe if you stay in the T1 hotel, you can use the swimming pool as well.
2. Walking the actual distance that the train covers should only be about 10 minutes. Also, I seem to remember that the travellators (moving walkways) have sensors, and will start either just before or when you get on them. Don't make the assumption that that they are broken or shut down if they're not running. Stupid me, that's what I did and thus did a lot of extra walking for no reason!