Abduction of the arm, as in raising a gun to start a race, occurs in which plane of motion?

Abduction of the arm, such as raising a gun to start a race, occurs in the frontal plane of motion. This plane separates the body into anterior (front) and posterior (back) sections and is primarily responsible for movements away from and towards the midline of the body. In this case, raising the arm away from the torso to start the race exemplifies an abduction movement, which increases the angle between the arm and the body in the frontal plane.

The sagittal plane, in contrast, would involve movements that go forward and backward, such as flexion and extension of the limbs. The transverse plane involves rotational movements around the axis of the body, which is not applicable to the action of raising an arm in a lateral manner. The term "rotational plane" is not typically recognized as a distinct plane of motion in this context, further differentiating the frontal plane as the correct classification for abduction.