The purpose of this study is to compare the effects of a balance reeducation protocol and an evidenced based protocol on pain, function and postural control of low back pain patients.

Both groups will perform general exercises for back pain (stretch and strength of paraspinal and abdominal muscles, plus exercises to enhance lumbar and pelvic flexibility but the balance or experimental group will perform in addition five minutes of exercises that challenge postural stability in the sitting position. The evolution of the two groups concerning pain level, function and postural control will be compared.

Inclusion Criteria:

• must have low back pain longer than three months and age between 40 and 69 years old

Exclusion Criteria:

• balance or neuromuscular disorders, spine surgery, diabetes.