If you look for  “hamstring stretches”  in Google Images, you’ll get a page full of illustrations most of which demonstrate what  I’m  trying to show you not to do in the accompanying video. This young man, for example, is mostly stretching his lower back and giving himself a crick in his neck.  How you position your pelvis and spine makes a huge difference in the effectiveness of your stretching.  I also hope to convince you that your hamstrings don’t exist in isolation in your body and that to lengthen them effectively involves changing how you use them in daily life…