The lower back muscles are an often neglected part of the core. It is not uncommon for trainees to put most of their focus and energy into their abdominal workout sessions, while forgetting about the erector spinae muscles of the lower back. Strengthening those muscles is important for good posture and core balance.

Hyperextension

The hyperextension exercise mainly involves the erector spinae. Place your thighs on the pad and your feet on the platform. Cross your arms in front of your chest. Lower your torso towards the ground by bending forward at the waist. Then go back up to the start. Keep the back straight throughout the movement. Advanced trainees looking to make the exercise more challenging may want to hold a weight in their hands during the exercise. Avoid bouncing at the bottom of the exercise.

Reverse Ball Hyperextension

A variation of the hyperextension can be performed on a stability ball. Lie, face down, with your stomach on top of your stability ball. Extend your arms, place your hands on the floor in front of the ball for support and extend your legs behind you with your toes on the floor. Slowly lift your legs until they are in line with your torso -- your body is in a straight line from your head to your heels. Pause for a count of two, slowly lower your legs back to the starting position and repeat. Avoid lifting your legs too high as this will cause your lower back to arch.

Full Deadlift

The barbell deadlift targets the erector spinae. It also involves the traps, quadriceps, hamstrings, glutes and rectus abdominis. Stand in front of the bar on the ground, bend down from the knees and lean your torso forward. Grab the bar with each hand with a grip that is shoulder-width apart. Keep the back straight and lift the bar up by extending the knees until your body is upright. Lower the bar back down by bending the knees and leaning the torso forward. Kip your hips low and your shoulders high throughout the lift. Avoid rounding your back and keep your knees pointing in the same direction as your toes.

Straight-Legged Deadlift

This exercise is a variation of the full deadlift. The movement works the erector spinae, hamstrings and glutes. Grab the bar with feet shoulder-width apart, tilt your tailbone back, stick your butt out and then stand upright and with legs straight. Keep your arms extended down and your back straight throughout the movement. Slowly bend forward at the waist until your torso is parallel to the floor. Raise your torso back up to the starting point. Keep looking up to make sure your back doesn't round and keep the bar over the top of your feet, close to legs. Do not pause or bounce at bottom of the lift.

Good Morning

Good mornings are for the erector spinae muscles, hamstrings and glutes. Grab the bar with both hands and place it on your upper back behind your head. Stand with your back and legs straight and put your feet together. Lean the torso forward by bending at the waist. Once your torso is parallel with the ground, go back to the upright position. Avoid rounding your back and concentrate on keeping you head up and eyes looking straight ahead throughout the exercise.