Which exercise is NOT recommended for improving endurance of back extensors?

Sit-ups are not recommended for improving the endurance of back extensors primarily because they primarily target the abdominal muscles rather than the muscles responsible for extending the back. The focus of sit-ups is to engage the rectus abdominis and obliques, with limited engagement of the back extensors.

In contrast, exercises like cat/cow, bird/dog, and prone head raises specifically emphasize the contraction and endurance of the back extensor muscles through movements that promote spinal extension and stabilization. These exercises are more effective for enhancing the strength and endurance of the muscles that support the spine in an upright position, making them suitable for developing back extensors.

Therefore, sit-ups do not contribute to the desired goal of improving back extensor endurance.