I altered the rotation. Each week I did three S90 workouts and two or three days of running or other workouts, for twelve weeks. I really enjoyed it. I felt like the S90 workouts did good things for my strength, cardio capacity, and balance. They work the core very well, and I also saw a bit more definition in my upper body.
When I finished my rotation, I still wasn't bored with the set. I could see myself doing it again. Not in the prescribed rotation, because I've learned that I need some free choice as well as structure to be consistent. But I think that using a modified S90 rotation as my "structure" worked very well
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