NSCF Certified Personal Trainer Practice Exam 2025 - Free Personal Trainer Practice Questions and Study Guide

The modified pull-up, where the feet are on the ground and the individual performs a supine pull-up, effectively targets the muscles involved in shoulder horizontal abduction. This movement primarily engages the back muscles, especially the rear deltoids and rhomboids, which are crucial for stabilizing the shoulder during various functional movements.

In terms of biomechanics, horizontal abduction occurs when the arms move away from the midline of the body while at shoulder height. The modified pull-up allows for a controlled environment to develop strength in this particular motion, improving overall upper body functionality, which is essential for activities requiring pulling of the arms back.

The other activities listed do offer benefits but are not as directly focused on horizontal abduction. For example, push-ups primarily engage the chest and triceps, seated rows emphasize the pulling motion without isolating the horizontal abduction angle, and standing shoulder presses target vertical lifting rather than the specific mechanics of horizontal movement. Thus, the modified pull-up is the most suitable option for enhancing shoulder horizontal abduction.