Your lower back muscles are part of the lumbo-pelvic-hip complex, or LPHC, a group of muscles and connective tissues in the abdominals, back and hips that supports your posture and generates strength. Since all muscles in the core work together to help you balance and move, you need to train the entire core rather than a specific area.
The LPHC is considered the core of the body, according to the National Academy of Sports Medicine. It absorbs and transfers energy during exercise and is the main source of strength and power. It consists of the inner unit, which stabilizes and maintains your center of gravity, and the outer unit, which moves your body. The inner unit includes the transversus abdominus, the external and internal obliques and the gluteal complex. The outer unit includes the rectus abdominus, erector spinae and hip flexors. All these muscles are attached to other muscles in the upper and lower body, affecting your mobility and strength.
The lower back muscles are the lower part of the outer spine muscles that move the torso in flexion and extension. When the deep stabilizing muscles in the spine, such as the multifidi, get weak from lack of use, the lower back muscles take over their job to stabilize. Constant use of the lower back, however, causes stiffness, pain and fatigue. Your lower back should function as a mover, not as a stabilizer.
Core strength training improves your ability to generate force without injuring yourself or losing balance. It teaches you how to move in various directions while maintaining your posture. When the inner unit is strong and stable, your lower back can do its job of moving the torso without injury and pain.
Most people who wants a stronger lower back do back-extension exercises on a machine, on the floor or on a stability ball. But core training should involve moving your body while maintaining your posture, not just working on your lower back or abs. Exercising only the lower back may cause a herniated disc or a tissue tear.
One simple exercise will strengthen your core without isolating your lower back. Lie on a stability ball facing downward, with your lower belly and pelvis on the ball, your chest off the ball and your feet slightly apart. Exhale and lift both arms above your head with your thumbs pointing up. Hold the position for one deep breath, then lower your arms in front of you. Lift your arms again and reach up to make a “Y” with your body. Hold for one deep breath, then lower your arms. Finally, lift your arms up behind your body, externally rotate them and point your thumbs up. Don’t arch or flex your spine at any point during this exercise.
About this Author
Nick Ng has been writing fitness related stories since 2003, focusing on nutrition, injury prevention and exercise strategies. He received his Bachelor of Arts in communications from San Diego State University in 2001 and has been a certified fitness coach from the National Academy of Sports Medicine since 2002.