Yesterday during my kettlebell class my instructor asked what workouts I did for the week and I said my normal KB and then I spent a few workouts (just walking) on the treadmill. She had a fit!!! She said you should NEVER go on a treadmill, it is horrible for you. I unfortunately didn't have a chance to ask her to explain since she had a group of folks waiting for their workshop, but I will definitely ask her next week to elaborate. In the meantime, I just wondered if any of you have ever heard such a thing and if so, why? I really love walking on the treadmill in the mornings at 5 AM (I kind of hate walking outside in the dark that early). I will ask her next week, but in the meantime the suspense is killing me. I would call but she left for Atlanta right after her workshop so I really won't get to chat with her until Sat.