Back belts are thought to act by decreasing spinal loading, decreasing vertebral compression, and increasing intra-abdominal pressure by limiting twisting and upper body gross motions. 2. They appear to have little effect on most back injury risk factors, but may have a limited effect on improving muscle strength and supporting the back during lifting and twisting activities. 3. The use of back belts as a psychological support requires further investigation. 4. Based on insufficient objective scientific data, NIOSH recommended against back belt use by healthy people.