Which term best describes a plane of motion characterized by forward and backward movement, such as during a squat or run?

• A. Frontal plane
• B. Medial
• C. Sagittal plane
• D. Lateral

Answer: (C)

Forward and backward movements, like those in a squat or running, happen in the sagittal plane. This plane runs from front to back and splits the body into left and right halves, and it’s where flexion and extension occur at the joints. In a squat, the hips and knees flex as you lower and then extend as you rise, all within that forward-backward range. Running involves the same kind of motion at the hip, knee, and ankle. The frontal plane, by contrast, handles side-to-side movements (abduction/adduction), and medial or lateral are directional terms related to the midline, not planes of motion.