I worked through the middle split workout today and I love it! I did have some trouble with a couple of exercises about which I would like some advice.
In the MSs/SE1 through SE3 exercises I felt a very unpleasant strain, pretty distinct from a 'normal' stretch, at the medial and posterior side of both of my knees when trying to extend the knee fully. Is this to be expected when starting out with these exercises? What struck me as very odd, was that I did not feel this strain at all (or at the very least at a very reduced intensity) with other exercises, not even with MSs/SE24 (isometric holds).