TRSE How To Draw Tutorials:
Various Poses of the Limbs
Step 3 of 5

    Notice the red line? That red line shows the muscles that are exposed when the arm is moved away from the body. Be sure to draw that muscle part when you're drawing a character with an arm help up in that position.
    Also, when an arm is raised toward the head, the arm pulls the chest muscles upward. Such pulling of the chest muscles lift the breasts (both male and female) a bit as shown in the picture. How much the breasts are lifted varies depending on the body and size of the breasts. This optional is recommended for those wanting their pictures to be as anatomically true as possible.