I set the treadmill for 30 minutes and bumped up the speed to 5.0. For me, 5.0 is a jog. That was my home base speed during my sprinting intervals. I never went below 5.0. This is where the playlist comes in:
I created a playlist of Britney Spears songs that really pick up during the chorus and slow down a bit during the verses. As the chorus approaches, I increased the speed as fast as I felt comfortable running. At the beginning of the workout, that was to 5.7. As the workout continued, I got up to 6.5. I never went slower than 5.0 and eventually kept my verse pace to about 5.4, depending on the speed of the song.
In 32 minutes (2 minutes to cool down), I burned 400 calories. Those 32 minutes went by really fast. I keep a towel over the screen of the treadmill so I can't focus on the time. Instead, I just listen to the music and play with the speed throughout the workout. I think I will create a few different playlists with different artists just to keep things fresh. I was surprised that I actually ran 30 minutes straight! I haven't done that in months!