Looking good, proportions are there, do note there's a little more flex - a little more angle - at the knee and ankle giving the pose a bit more dynamism
As an experiment, try out doing one of these studies using mostly straight lines (short and long) and once you have the sketch done, go over those lines a second time to give them a little more weight towards the darker side of the figure
Curved cylinders can be so hard to make look good, but seem so simple in principle XD keep at it, when in doubt or having trouble on those, it helps first draw a line in the middle (like a spine) and to draw various contour ellipses along the cylinder to help better visualize it as you work on them
cheers!