What muscle group is the primary mover during a lunge?

In the context of a lunge, the primary mover, or agonist muscle, is predominantly the glutes. During a lunge, as you lower your body and push back up, the glute muscles (especially the gluteus maximus) are heavily involved in extending the hip joint. This movement is crucial for the upward phase of the lunge, where you return to a standing position, and the glutes are responsible for driving that motion.

While the quadriceps and hamstrings certainly play supportive roles—such as stabilizing the knee and assisting in movement—the glutes are the key muscles executing the primary action. Therefore, recognizing the glutes as the main driver of the lunge movement reflects an understanding of muscle engagement during functional exercises.

Choosing "None of the above" as the answer overlooks the significant role that the glutes play in lunges, including their responsibility for hip extension, which is fundamental to the lunge's mechanics.