Windshield wipers are the closest thing we do to a dedicated abdominal exercise in Primal Rotational Patterns. The exercise is part crunch, part side bending, and all rotation of the abdominal core.
It bears noting that in a Primal Rotational Patterns session, we do only one set of each exercise. This is to serve the goal of maximally impacting all the fascia each workout. There are many other exercises that impact the abdominals that we also do.
In fact, you cannot do any movement without using the abdominals because force is translated from lower to upper body and vice versa through the core. That said, Primal Rotational Patterns is not an abs class. If you want abs that perform as well as they look, come here. If you are looking for fitness-through-body-part-neuroses, please go elsewhere.
Windshield Wipers Performance
Begin by lying supine (on your back) and spreading the arms palms-up so that the palms’ centers are in line with your shoulders.
Flex the hips to 90˚. This makes the thighs perpendicular to the floor.
Flex the knees the appropriate angle as detailed in your WID #. Changing knee flexion provides different levels of overload to different parts of the musculature.
As the timer expires, begin rotating the lower body across your midline. The easiest way to begin to initiate this movement is by “rotating” the knees left or right, but with practice you develop the awareness and ability to begin rotation by initiating the movement from the anterior blade of the pelvis.
This part of the pelvis is the anterior inferior iliac spine. It should lift off the floor / table and immediately begin to rotate around its opposite counterpart. The legs should travel with it as a unit, with the top leg working in propulsion of the thigh to keep the movement pure and reduce shearing of the pelvis. This process causes spinal rotation to occurs through the entire thoracic and cervical spine.
Depending on whether the knees or the feet are in the lead of the exercise (as dictated by the position of the legs), direct them toward the palm of your hand across your midline. You do not need to reach the palm; you need to move toward it. When range is exhausted, return to the beginning position.