My current fave
In my log I call this my 5 minute intervals workout, although it isn't a classic interval type of workout. I had to call it something other than "that thing I like to do on the treadmill in 5 minute cycles."
1. 5 minutes -- warm up on 0% grade, starting at 3.8 and ending up at about 4.5
2. 5 minutes -- 1% grade, 6.5 mph
3. 5 minutes -- 0% grade, 7 mph
4. 5 minutes -- 6% grade, 4.3 mph
5. 5 minutes -- 4% grade, 4.8 mph
6. Repeat steps 2 - 5
7. 5 minutes -- 1% grade, 6.5 mph
8. 2.5 minutes -- 0% grade, 7 mph
9. 1.5 minutes -- 0% grade, 7.5 mph
10. 1 minute -- 0% grade, 8 mph
11. 5 minutes cooldown gradually reducing speed.
12. Stretching off the treadmill.
I always feel really good when I finish this workout. Minus the stretching it clocks in at 1 hour. My knees like it better than a 60 minute straight jog/run, and according to my treadmill ( for whatever it's worth ) I burn more calories doing these cycles than a straight run as well. While it isn't exactly an interval workout, I treat it as one in my workout schedule. So if I do this, I follow it with a light day and don't do another interval workout for the next few days.
I can't wait to see other people's suggestions!
Erin