I like certain tunes for different phases of treadmill/elliptical workout. When I get to something in the Celtic rock range, like “Sunday Bloody Sunday” by U2 or Aztec Camera with Mick Jones “Good Morning, Britain,” it’s perfect to do a steep incline and slower, bigger steps. 80s ska is great to get the speed up. I generally put the iPod Shuffle on random and occasionally flip ahead if a song doesn’t fit the mood, but even a slower song can go with fast walking if I’m in the zone.