Also called lower back muscles, spinal erectors, back extensors
The erector spinae are three columns of muscle running up either side of the spine, from the sacrum and pelvis to the ribs, neck and skull: the iliocostalis on the outside, the longissimus in the middle, and the spinalis closest to the spine.
They are the main muscles that straighten the back, and just as importantly they lower you under control when you bend forward.
Bird dogs produced high iliocostalis activity with a low spinal load, and a bridge with one leg lifted gave the most erector activity among stabilisation exercises. Back extensions work them hardest of the four back exercises tested, with the most spinal compression, so progress gradually.
These are standard low-back stretches from NHS physiotherapy leaflets. They bend the spine the opposite way to this muscle's action; no study has named them as stretches for it.
The low-back muscles are a common source of back pain and can go into painful spasm; muscular back pain is treated conservatively.
What role the muscles play over time is less clear. A review found moderate evidence of multifidus shrinkage in chronic back pain, but results for the erector spinae were inconclusive. Good back-muscle endurance was associated with fewer first episodes of back trouble in men, and weak endurance with back pain, though associations are not proof of cause.
Back pain needs a special muscle-targeting programmeStrong evidence
NICE recommends considering group exercise of whatever type suits the person, and a Cochrane review found no single type of exercise clearly better. Strength and endurance work is reasonable; no one muscle has been shown to be the cause.
Anatomy and movement education, not a diagnosis or treatment plan. If you have pain that follows an injury, is severe or getting worse, or comes with numbness, weakness or swelling, get it assessed. Health disclaimer.
