Which stretch is commonly referred to as the "World's Greatest" and warms up the lower body and hips?

The "World's Greatest" stretch refers to the Runner's Lunge. This dynamic stretching exercise effectively targets the lower body and the hips, making it an excellent warm-up movement. It involves transitioning through a lunge position while emphasizing mobility in the hip flexors and hamstrings, along with promoting thoracic spine rotation.

This stretch is particularly beneficial because it integrates multiple muscle groups and enhances flexibility as well as stability. Engaging in the Runner's Lunge helps to prepare the body for various activities, especially those involving lower body movement, by improving range of motion in the hips and activating the core and legs simultaneously.

In contrast, other options focus on different areas of conditioning or training. Navasana is a core-strengthening yoga pose rather than a dynamic stretch. Wall Drill is typically associated with speed and agility training rather than a comprehensive full-body warm-up. The Pro Agility Test is a measurement of agility and speed, which doesn’t specifically function as a warm-up stretch for the lower body and hips. Hence, the Runner's Lunge stands out as the most appropriate choice for this context.