What is the primary muscle focus during the Roll Up exercise?

The Roll Up exercise primarily targets the abdominals, emphasizing their role in spine articulation. During this movement, the focus is on engaging the core muscles to control the flexion and extension of the spine as you roll up from a supine position to a seated position and then return. This not only strengthens the abdominal muscles but also promotes flexibility in the spine, enhancing coordination and posture.

In contrast, while the leg muscles provide stability during the exercise, their involvement is secondary to the primary focus on the abdominals. The back muscles may assist in supporting the movement, but they are not the central focus in the Roll Up itself. Similarly, the shoulders play a supportive role in maintaining proper form, rather than being the primary target. This makes the abdominals the key muscle group engaged in this exercise, which aligns perfectly with the correct answer.