During the hamstring stretch, the recruit attempts to touch the floor with their hands by bending at which part of the body?

The hamstring stretch primarily involves bending at the waist. This movement allows for a more effective elongation of the hamstring muscles situated at the back of the thigh. By bending at the waist, the recruit can engage the hip joint, which facilitates a deeper stretch of the hamstrings as well as the lower back. This position is crucial for maximizing the effectiveness of the stretch while ensuring proper body mechanics are maintained.

Bending at the knees, for instance, would limit the stretch and might not provide the intended benefit to the hamstring muscles. Flexing at the hips is indeed part of this motion but is primarily guided by the pivot at the waist, hence why the waist is the most relevant part of the body in this context. Reaching down towards the ankles typically occurs at the end of the stretch but is not as instrumental in the actual process of elongating the muscles during the stretch itself.