A great test for any fighting pose is to fill it in completely with black. If you can still tell exactly what the character is doing just by looking at the black shape, you have a strong silhouette. If the silhouette is a confusing blob, you need to adjust the limbs to make the action clearer.
In the context of fighting poses, this highlights the necessity of exaggeration. In a real fight, movements are often too fast and compact to be visually clear in a still image. Artists must "cheat" the anatomy to make the action readable. A punch might be drawn with a slightly longer reach than physically possible to emphasize the extension. A recoil might be exaggerated to show the weight of the impact. By comparing the reference photos to the artists' interpretations, the reader learns that anatomy is not a rigid cage, but a flexible framework to be pushed and pulled for dramatic effect.
While Book 6 was originally released as a standalone volume, it is now frequently found as part of , a massive 900+ page compilation.
Use the PDF in split-screen mode. On one side, have the fighting pose. On the other side, have a blank canvas. Trace only the skeletal structure first. Then, add the muscle blocks. Finally, draw the skin contour. This builds anatomical memory.