Which exercise focuses on arm movement from the face cheek to the butt cheek?

The exercise that focuses on arm movement from the face cheek to the butt cheek is stationary arms. This refers to a stance where the arms are kept motionless while performing other movements such as leg exercises or bodyweight activities. The concept of moving from the "face cheek to the butt cheek" highlights a range of motion where the arms travel along the side of the body, which is characteristic of this exercise stance.

In contrast, other options involve distinct movements that do not fit the description. For example, during a bicep curl, the focus is primarily on flexing the elbow and raising the forearms towards the shoulders, which does not correlate with moving from cheek to cheek. Similarly, tricep extensions focus on extending the arm at the elbow, typically in an overhead or backward motion rather than across the body. Seated leg curls, on the other hand, are dedicated to targeting the hamstrings and do not involve arm movement at all. Thus, stationary arms is the choice that accurately represents the described movement.