What is the fixator in a press up?

In a press-up, the fixator muscles are those that stabilize the body during the movement. Primarily, the core muscles, including the rectus abdominis and obliques, act as fixators to maintain proper alignment and stability of the torso. Additionally, the muscles of the shoulders, such as the rotator cuff, help stabilize the shoulder joint throughout the exercise. This stabilization allows for effective movement of the arms while minimizing the risk of injury.