Right trunk rotation in the transverse plane is best described as what type of motion?

• A. +θY
• B. −θY
• C. +θZ
• D. −θZ

Answer: (B)

Right trunk rotation in the transverse plane describes a motion that occurs about the vertical axis of the body, which is typically represented by the Z-axis in three-dimensional coordinate systems. In biomechanics, positive and negative angular displacements can be defined based on the direction of motion.

For trunk rotation toward the right, this motion is typically classified as a negative rotation about the Z-axis. This is because, when viewed from above, a clockwise rotation (like turning to the right) is often considered a negative angular motion in right-handed coordinate systems. Thus, the correct description of right trunk rotation aligns with the concept of negative rotation about the Z-axis, accurately conveying the direction and type of motion taking place.