Jenn-I've used iTread 6 outdoors twice. I was concerned how it would be, but I LOVED IT! Try it out. I usually do iTreads indoors on the TM, and this was my first outdoor iTread. I was happily surprised. For different intervals, she has you pick something in front of you...a bridge, a mailbox, a tree, etc...and run at a certain intensity level till you get to (or beyond) that point. I really did like it!
Gayle