Author(s): McGill SM
Despite the wide variety of exercises that are prescribed for the low back, the scientific foundation to justify their choice is not as complete as one may think, or expect. Thus, the clinician must often call upon "clinical opinion" when selecting exercise. Given that low back tissues may need stressing to enhance their health but too much loading can be detrimental, choosing the optimal exercise requires judgment based on clinical experience and scientific evidence. To assist in developing better exercise programs, this review documents some recent biomechanical evidence from my laboratory and from laboratories of other researchers that has been reported in various publications in an attempt to update clinicians on issues of low back exercise. Among the issues examined are mechanisms of injury; the relative importance of "strength" (ie, maximum force a muscle can produce during a single exertion to create joint torque), "flexibility," and "endurance"; and training to enhance stability. Finally, some specific exercises are described that have been shown to challenge muscle and enhance performance but that are performed in such a way as to minimize loading of the spine to reduce the risk of injury exacerbation. These exercises form a basic program for rehabilitation and maintenance of low back health.