No matter the body, the basic building blocks are always the same. Not everyone has to be super athletic.
You can vary the overall height of your characters.
And even at this early stage you can make characters look older using posture, or younger. A big head and smaller body is a great hack for drawing children.
See how far you can push the shapes and exaggerate the form.
Remember... the body is nothing more than a series of basic shapes combined together to create a figure. These shapes are grouped into 6 key areas...
But feel free to bend these rules. In some cases the torso can be made of just two sections.