ACSM Personal Trainer Certification Practice Exam 2025 - Free Personal Trainer Practice Questions and Study Guide

The sagittal plane is the correct choice because it specifically divides the body into left and right segments. This plane runs vertically from front to back, allowing for movements that occur forwards and backwards—such as walking and running—to be analyzed in this context.

In contrast, the frontal plane, also known as the coronal plane, divides the body into anterior (front) and posterior (back) sections. This plane is involved in movements that occur side to side, like jumping jacks or lateral arm raises.

The horizontal plane, or transverse plane, divides the body into superior (upper) and inferior (lower) segments. Movements occurring in this plane typically involve rotational actions, such as twisting the torso.

Finally, the term "transverse plane" is synonymous with the horizontal plane and, like that, it focuses on horizontal movements rather than the vertical division of the body into left and right parts that the sagittal plane describes. Therefore, the definition and function of the sagittal plane make it the clear answer for dividing the body into left and right sections.