The back extension machine is a piece of equipment commonly found in gyms that specifically targets the muscles of the lower back. Here is how to perform the exercise on a back extension machine: 1. Adjust the machine: Start by adjusting the height of the footplate or pad so that it aligns with your hips or lower waist when you are standing in front of the machine. 2. Position yourself: Stand in front of the machine facing away from it and place your feet shoulder-width apart on the footplate or pad. Your toes should be pointing forward or slightly outward. 3. Engage your core: Place your hands on your hips or cross them over your chest. Engage your core muscles by pulling your belly button in towards your spine. 4. Lower your upper body: Slowly lower your upper body towards the floor by hinging at your hips. Keep your back straight and avoid rounding your shoulders. 5. Extend your back: Once your upper body is parallel to the floor, slowly lift it back up by extending your lower back. Squeeze your glutes and lower back muscles as you lift. 6. Repeat: Perform the desired number of repetitions, usually 10-15, or as recommended by your fitness trainer or program.