This site is very cool and useful! I'm using it to support my progress through Nicolaides' "The natural way to draw. But before I take out a subscription I'd like to know if you have moving action poses that can be looped so that I can practice the moving action drawings that Nico recommends - I've tried different ways with youtube videos but it's too complicated and I'm not yet good enough to do this in real life.
Nice way to ask, Zalamander, but in order to study your moving action poses, then you can just capture the movements of the poses' forces over forms by watching it in movement while you sketch them out blindly, while on tablets'/phone's timer app, but also you can just pause the video frame by frame to just capture the gestures, yet not just the forms and details. If you really need to loosen up your gestures and simple forces, then I'd recommend you do 5 minutes of 30 second poses, because if you do 30 seconds per pose, then your lines of action will become strongly looser for your simpler foundations.
For even more details, please look into this video tutorial on how to study your Youtube videos frame by frame. Here:
Hope these things have become completely, totally, truly and absolutely useful to your learning curves and marches of progress.