Conclusions Leisure time physical activity may reduce the risk of chronic LBP by 11%–16 % .
Background There are plausible mechanisms whereby leisure time physical activity may protect against  low back pain ( LBP )  but there have been no quality systematic review s and meta-analyses of the subject .
Objective This review aims to assess the effect of leisure time physical activity on non-specific LBP .
Active Therapy for Chronic Low Back Pain: Part 3. Factors Influencing Self-Rated Disability and Its Change Following Therapy
Design . Cross-sectional analysis of the factors influencing  self-rated disability associated with chronic low back pain and prospect i ve study of the relationship between changes in each of these factors and in disability following active therapy . Objectives . To examine the relative influences of pain , psychological factors , and physiological factors on self-rated disability . Summary of Background Data . In chronic LBP , the interrelationship between physical impairment , pain , and disability is particularly complicated , due to the influence of various psychological factors and the lack of unequivocal methods for assessing impairment . Investigations using new “ belief ” question naires and “ sophisticated ” performance tests , which have shown promise as discriminating measures of impairment , may assist in clarifying the situation . Previous studies have rarely investigated all these factors simultaneously . Methods . One hundred forty-eight patients with cLBP completed question naires and underwent tests of mobility , strength , muscle activation , and fatigability , and ( in a subgroup ) erector spinae size and fiber size/type distribution . All measures were repeated after 3 months active therapy . Relationships between each factor and self-rated disability ( Rol and and Morris question naire ) at baseline , and between the changes in each factor and changes in disability following therapy , were examined . Results . Stepwise linear regression showed that the most significant predictors of disability at baseline were , in decreasing order of importance : pain ; psychological distress ; fear-avoidance beliefs ; muscle activation levels ; lumbar range of motion ; gender . Only changes in pain , psychological distress , and fear-avoidance beliefs significantly accounted for the changes in disability following therapy . Conclusion . A combination of pain , psychological and physiological factors was best able to predict baseline disability , although its decrease following therapy was determined only by reductions in pain and psychological variables . The active therapy programm — in addition to improving physical function — appeared capable of modifying important psychological factors , possibly as a result of the positive experience of completing the prescribed exercises without undue harm
Conclusions Leisure time physical activity may reduce the risk of chronic LBP by 11%–16 % .
Background There are plausible mechanisms whereby leisure time physical activity may protect against  low back pain ( LBP )  but there have been no quality systematic review s and meta-analyses of the subject .
Objective This review aims to assess the effect of leisure time physical activity on non-specific LBP .