Movement and Rotation in Planes and Axes
Plane of movement
A plane of movement is an imaginary flat surface that divides the body into sections and along which movements occur.
- Movements occur within a plane and are controlled by the muscles, joints, and nervous system.
- Each plane allows specific types of movement, and understanding them is crucial for analyzing human motion in sports and exercise.
Anatomical Plane
An imaginary flat surface used to divide the body for anatomical study and movement analysis. The main anatomical planes are: Sagittal Plane, Frontal (Coronal) Plane and Transverse Plane
- Consider the body is moving between three sheets of glass, one slicing from front to back, another from side to side, and the third cutting horizontally.
- Each movement must follow the direction allowed by the glass.
The Three Anatomical Planes
- The human body moves in three anatomical planes: sagittal, frontal, and transverse.
- Each plane allows different types of movement.
1. Sagittal Plane
- The sagittal plane divides the body into left and right halves.
- Movements in this plane occur forward and backward and involve changes in joint angles.
In a squat:
- Knee flexion during descent
- Hip flexion as you lower
- Both knee and hip extension as you rise
- All movement occurs in the sagittal plane
Common Movements in the Sagittal Plane
- Flexion: Decreasing the angle between two bones (e.g., bending the knee in a squat).
- Extension: Increasing the angle between two bones (e.g., straightening the knee in a squat).
- Dorsiflexion: Lifting the toes towards the shin (e.g., during the back phase of a running stride).
- Plantarflexion: Pointing the toes downward (e.g., pushing off in a sprint start).
Examples in Sports:
- Running: The legs and arms move forward and backward in the sagittal plane.
- Cycling: The knees flex and extend during each pedal stroke.
- Weightlifting: Movements such as deadlifts, lunges, and squats occur primarily in this plane.
- Students often confuse flexion and extension.
- A simple rule: Flexion makes the joint angle smaller, extension makes it larger.
If a movement occurs in the sagittal plane, the axis of rotation is perpendicular to it, in this case, the frontal axis.
2. Frontal Plane
- The frontal plane divides the body into front (anterior) and back (posterior) halves.
- Movements in this plane occur side-to-side.
Common Movements in the Frontal Plane
- Abduction: Moving a body part away from the midline (e.g., raising the arms in a lateral raise).
- Adduction: Moving a body part toward the midline (e.g., bringing the arms back down in a lateral raise).
- Inversion: Turning the sole of the foot inward (e.g., rolling an ankle).
- Eversion: Turning the sole of the foot outward.
- Elevation: Raising a body part (e.g., shrugging the shoulders).
- Depression: Lowering a body part (e.g., dropping the shoulders).
Examples in Sports:
- Jumping Jacks: The arms and legs move in the frontal plane.
- Side Lunges: Movement occurs side-to-side.
- Defense in Basketball: Lateral shuffling is an example of movement in the frontal plane.
A good way to remember this plane is to consider standing between two glass walls, you can move side-to-side, but not forward or backward.
3. Transverse Plane
- The transverse plane divides the body into top (superior) and bottom (inferior) halves.
- Movements in this plane involve rotation.
Common Movements in the Transverse Plane
- Rotation: Twisting a body part around its axis (e.g., turning the head side to side).
- Pronation: Rotating the forearm so the palm faces downward.
- Supination: Rotating the forearm so the palm faces upward.
- Horizontal Flexion: Moving the arm across the body at shoulder level (e.g., chest fly).
- Horizontal Extension: Moving the arm away from the body at shoulder level.
- The transverse plane is like a tabletop slicing through your waist.
- Movements in this plane involve rotation, such as turning your head or twisting your torso.
Examples in Sports:
- Golf Swing: The torso rotates in the transverse plane.
- Baseball Pitch: The shoulders and torso rotate.
- Tennis Forehand: The hips, torso, and shoulders rotate in the transverse plane.
Students often confuse planes with axes. Remember: Movement occurs IN a plane but AROUND an axis. Like a door swings in a plane but rotates around its hinges (axis).
Axes of Rotation
Axis of rotation
An axis of rotation is an imaginary line around which movement occurs.
Each movement in a plane occurs around an axis that is perpendicular to that plane.
Analogy- Consider a hinge on a door.
- The door moves around the hinge, just like body parts move around an axis.
1. Sagittal Axis (Anteroposterior Axis)
- Runs front to back through the body.
- Perpendicular to the frontal plane.
- Movements around this axis include abduction and adduction.
- A cartwheel occurs around the sagittal axis.
- A side lunge moves around the sagittal axis.
- A jumping jack rotates around this axis.
Many students assume the sagittal axis is related to the sagittal plane, but it is actually perpendicular to the frontal plane and controls side-to-side movements.
2. Frontal Axis (Mediolateral Axis)
- Runs side to side through the body.
- Perpendicular to the sagittal plane.
- Movements around this axis include flexion and extension.
- A somersault occurs around the frontal axis.
- A bicep curl involves rotation around the frontal axis.
- A squat moves around the frontal axis.
Since this axis runs side to side, it is always related to forward and backward movement.
3. Longitudinal Axis (Vertical Axis)
- Runs top to bottom through the body.
- Perpendicular to the transverse plane.
- Movements around this axis involve rotation.
- A ballet pirouette occurs around the vertical axis.
- A discus throw rotates around the vertical axis.
- A golf swing moves around the vertical axis.
Think of supination as holding a bowl of soup with your palm up.
Common MistakeStudents sometimes confuse plane and axis. Always remember:
- Movement happens in a plane.
- Rotation happens around an axis.
Types of Movements and Their Planes
Types of Movements in the Sagittal Plane
1. Flexion
Flexion
A movement that decreases the angle between two bones at a joint.
- Typically moves a limb forward (except for the knee, which moves backward).
- Involves muscle contraction that brings bones closer together.
Common movements with flexion:
- Elbow Flexion: Bending the arm during a bicep curl.
