标题：Effects of Recreational Physical Activity and Back Exercises on Low Back Pain and Psychological Distress: Findings From the UCLA Low Back Pain Study
摘要：Objectives. We sought to estimate the effects of recreational physical activity and back exercises on low back pain, related disability, and psychological distress among patients randomized to chiropractic or medical care in a managed care setting. Methods. Low back pain patients (n=681) were randomized and followed for 18 months. Participation in recreational physical activities, use of back exercises, and low back pain, related disability, and psychological distress were measured at baseline, at 6 weeks, and at 6, 12, and 18 months. Multivariate logistic regression modeling was used to estimate adjusted associations of physical activity and back exercises with concurrent and subsequent pain, disability, and psychological distress. Results. Participation in recreational physical activities was inversely associated—both cross-sectionally and longitudinally—with low back pain, related disability, and psychological distress. By contrast, back exercise was positively associated—both cross-sectionally and longitudinally—with low back pain and related disability. Conclusions. These results suggest that individuals with low back pain should refrain from specific back exercises and instead focus on nonspecific physical activities to reduce pain and improve psychological health. Low back pain is one of the leading reasons for physician visits 1 and is the most common reason for use of complementary and alternative medicine in the United States. 2 Back symptoms are frequently accompanied by depression or anxiety and psychological distress, 3 , 4 which are principal reasons for use of both conventional and complementary health care. 1 , 2 Despite the well-known cardiovascular and weight control benefits of regular physical exercise, participation has decreased in recent years, 5 with almost 70% of US adults reporting that they do not engage in regular leisure-time physical activity. 6 Findings from several studies conducted in the United States and elsewhere have shown associations of physical activity with depression and psychological well-being, 7 – 16 as well as the potential buffering effects of physical fitness or activity on stress. 17 – 21 Exercise interventions have been shown in some randomized clinical trials (RCTs) to help prevent low back pain in at-risk populations. 22 However, the bulk of the scientific literature indicates that specific back exercises (e.g., flexion, extension, and strengthening exercises) and instruction in standardized exercises (as advocated by many physical therapists) do not appreciably improve low back pain prognoses. 23 , 24 Although the results of observational studies have not been entirely consistent (e.g., Kujala et al. 25 ), these investigations have produced evidence pointing to the benefits of leisure-time physical activity in preventing low back pain or improving its prognosis. 26 – 31 In addition, various published guidelines 32 , 33 recommend that patients with acute low back pain stay active, and a recent systematic review of RCTs provided corroboration for such a strategy. 34 Nevertheless, no published studies have followed a clinical population over an extended period and collected serial data on reported use of back exercises and leisure time physical activity to estimate separate and unconfounded associations of physical activity and exercise with concurrent and subsequent low back pain, disability, and psychological distress. We sought to estimate the effects on several outcomes of recreational physical activity and back exercise among low back pain patients participating in a large RCT conducted in a managed care setting. We hypothesized that (1) participation in sport or recreational physical activities would reduce levels of low back pain, disability, and psychological distress and (2) back exercises would not reduce levels of pain, disability, and psychological distress.
