📖 Read-only demo. All content is browsable; accounts, saved progress, and quizzes need the full app — run it locally from GitHub.

Skip to content
beginnerSource-checked10 min read

Body Planes and Axes

The three flat 'slices' used to describe the direction a movement happens in.

Before this: Anatomical Position and Directional Terms

You will be able to

  • Name the three anatomical planes.
  • Match each plane to the movements that occur in it.
  • Explain what an axis of rotation is.
A stylized standing human figure with three intersecting planes: a vertical sagittal plane splitting left and right, a vertical frontal plane splitting front and back, and a horizontal transverse plane splitting top and bottom.
The three anatomical planes. Shows how the sagittal, frontal (coronal), and transverse planes divide the body, used to describe the plane a movement happens in.
Illustration: Anatomy Learning Platform (original) · CC0-1.0 (public domain dedication)

Planes: imaginary slices through the body

A plane is a flat surface that cuts through the body. We use three:

  • Sagittal plane — a vertical slice that divides the body into left and right. Forward/backward movements (like a biceps curl or walking) happen here.
  • Frontal (coronal) plane — a vertical slice that divides the body into front and back. Side-to-side movements (like raising your arms out to the sides) happen here.
  • Transverse plane — a horizontal slice that divides the body into top and bottom. Rotational movements (like twisting the torso) happen here.

Axes: the lines movement turns around

Every rotation happens around an axis — an imaginary line the movement pivots on, like the pin in a door hinge. Each plane has an axis at right angles to it. You do not need to master axes yet; just know that "plane" describes the direction of a movement and "axis" describes the line it rotates around.

Why this matters for training

Describing an exercise by its plane helps you balance a program. Many everyday exercises happen in the sagittal plane; adding frontal-plane and transverse-plane work trains the body more completely.

Sources for this lesson

“The sagittal, frontal (coronal), and transverse planes are the standard anatomical planes used to describe the body and its movements.”

Anatomy and Physiology 2e — OpenStax, Rice University · Ch. 1.6 Anatomical Terminology (Anatomical Planes)

Peer-reviewed textbook · License: CC BY-NC-SA 4.0 · Last checked 2026-07-19

Take the quiz (1 questions)

Sign in to mark this complete, bookmark it, and save private notes.