We all know that the hams are more hip extensors than knee flexors, but does that mean that knee flexion exercises should be kicked-out tottaly? Without GHR (glute ham raise), what would you siggest for knee flexion? leg curls? Is there any real need for this exercise? I dont use it… just RDL and other stuff
You can use a slideboard leg curl, a stability ball hip extention+curl, or even a stepping on a towel and curling while extending on a marble/tile floor. All of which train both hip extention and flexion, so you are not missing either component. The only difficulty is adding resistance to these movements. Only thing I can see here is perhaps adding band tension from the side across from your body.