Back extensions use the erector spinae, a three-part muscle comprised of the iliocostalis, spinalis and longissimus. The erector spinae is responsible for both flexion and lateral flexion of the spine. Done properly, back extensions specifically target this muscle, strengthening your lower back.

Muscle group: Back

Steps

If you’re using a back extension machine with a weight stack for the first time, start with a low weight and work on your form. Sit on the seat and position the roller against your shoulder blades. Slide your shoulders down and keep your chest lifted as you lean back. Don’t go all the way to horizontal. Return to your original position with control. Over time, you can slowly add weight. In his book "Strength Training Anatomy," Frederic Delavier calls back extensions a great exercise for beginners. He recommends doing sets of 10 to 12 repetitions. Monitor how your back is responding. If you feel pain, this might not be the back exercise for you.

All exercises