if you don't want to blow your ear drums (because that's not cool) on your morning run into work via the tube network. One suggestion. don't listen to to Rock. if all the music on my iPod - it's rock that you HAVE to turn up to really hear it properly. other music you can hear quite reasonably without cranking up the volume until your eyes pop out of your head. I'm thinking it's probably dude to the dependence of rock on background music and fuzz which quickly gets drowned out by the sound of the tube - so you turn it up.

don't hurt your ears - you'll only feel the hurt in 20 years time.