I am doing something like the top example. I don't think there's anything wrong with the second example in principle. I feel like for a high-resistance band, it would be hard to keep the band you're standing on under your foot instead of sliding out and snapping up to hit you. Also, the part of the band on the ankle of the curling leg would slip up your calf. But I have not tried it - I don't have those kinds of bands. For this exercise, I'm using the heaviest band I have, which is labeled as 23 lb, although I'm not sure exactly what that means.