Getting back into figure drawing

Figure drawing is a big challenge for me.  I was always a little intimidated by it, maybe because of the way I was originally taught.  I want to start over and explore the body beginning with skeletal structure and muscles and move on from there.  A large part of my confusion with figure drawing was not understanding basic body construction.  I don't want to worry about getting too detailed, so I'll focus on the main body masses, joints, long bones and extremities.  When you break it down like that, it's easier to remember and it sort of goes in sets of threes:

• head, ribcage, and pelvis
• shoulder, elbow, and wrist 
• humerus, radius/ulna, and hand 
• hip, knee, and ankle 
• femur, tibia/fibula, and foot

So for any figure you want to draw, you put in the basic structural elements and then build on them which keeps your proportions correct.

Starting off with Mr. Skeleton, we can see the basic shapes of these elements:

Things to notice:

• The whole figure is about 7 1/2 or 8 'heads' high.  This is a pretty standard way to measure the human figure when upright and gives you some measurements to work with.  The top three 'heads' include the head, neck, chest and most of the spine.  The forth head is the pelvis, the fifth and sixth are the femur and knees and the 7th down are everything below the knee.
• Our limbs are very similar in terms of bone and joint structure.  The shoulder and hip joints are ball joints and have the most free degree of motion.  The knee and elbow joints are hinge joints and have about 180 degrees of motion along a singular plane.  The more limited range of motion in the knee and elbow provide more strength and stability.  The joints of the wrist and ankle are a little more complicated, but are similar to each other and have a very high degree of range of motion.  Looking at the bones of the arms and legs, you can see the similarities there as well between the femur and humerus, between the radius & ulna/tibia & fibula and between the bones of the hands and feet.
• The structure of the shoulders and hips mean that they will always be in line with each other and create angles that will help to place the positions of the other bones and joints.
• For drawing purposes, the most difficult areas to draw are the ones with the most parts and details (the face, hands and feet), so those can be represented by simple shapes so you can keep drawing without agonizing about those areas.

Now moving on to Mr. Muscles, you can place the same elements on a body with muscles added on to the skeleton and see how they look.  Side by side with and without a picture for reference: 

To get the basics of figure drawing down, you can simplify this even further by drawing these stick figure sort of people using basic ovals and lines to place the figure in a 3D environment with gravity and body motion.  A good starting place is to draw a shape like a capital I representing the shoulders, spine and hips.  (Wider shoulders will look more masculine while wider hips will look more feminine.)  The angle of the shoulders and hips and the curve of the spine will define the pose and help fill in the limbs and head.

Some dancing stick figures: