The impact of stretching on sports injury risk: a systematic review of the literature,”

. Purpose: We conducted a systematic review to assess the evidence for the effectiveness of stretching as a tool to prevent injuries in sports and to make recommendations for research and prevention. Methods: Without language limitations, we searched electronic data bases, including MEDLINE (1966), Current Contents (1997), Biomedical Collection (1993, the Cochrane Library, and SPORTDiscus, and then identified citations from papers retrieved and contacted experts in the field. Meta-analysis was limited to randomized trials or cohort studies for interventions that included stretching. Studies were excluded that lacked controls, in which stretching could not be assessed independently, or where studies did not include subjects in sporting or fitness activities. All articles were screened initially by one author. Six of 361 identified articles compared stretching with other methods to prevent injury. Data were abstracted by one author and then reviewed independently by three others. Data quality was assessed independently by three authors using a previously standardized instrument, and reviewers met to reconcile substantive differences in interpretation. We calculated weighted pooled odds ratios based on an intention-to-treat analysis as well as subgroup analyses by quality score and study design. Results: Stretching was not significantly associated with a reduction in total injuries (OR ϭ 0.93, CI 0.78 -1.11) and similar findings were seen in the subgroup analyses. Conclusion: There is not sufficient evidence to endorse or discontinue routine stretching before or after exercise to prevent injury among competitive or recreational athletes. Further research, especially well-conducted randomized controlled trials, is urgently needed to determine the proper role of stretching in sports. Key Words: ATHLETES, CONDITIONING, META-ANALYSIS, SYNTHESIS S tretching before participation in athletic activities is standard practice for all levels of sports, competitive or recreational. Athletes, coaches, trainers, physiotherapists, and physicians recommend stretching in an effort to both prevent injury and enhance performance; numerous journal articles and textbooks are devoted to the topic, providing a variety of approaches directed to different parts of the body and for specific sporting activities (1). As more people participate in sports and other recreational activities through social changes (e.g., Title IX) and increased recognition that physical activity is part of a healthy lifestyle, injury prevention becomes more important. However, some investigators have questioned the routine practice of stretching and contend that there is little evidence that stretching pre-or postparticipation prevents injury and that it might affect performance negatively We developed a logic model to illustrate the relations among stretching, flexibility, performance, and injury (Fig

The impact of stretching on sports injury risk: a systematic review of the literature,”

. Purpose: We conducted a systematic review to assess the evidence for the effectiveness of stretching as a tool to prevent injuries in sports and to make recommendations for research and prevention. Methods: Without language limitations, we searched electronic data bases, including MEDLINE (1966), Current Contents (1997), Biomedical Collection (1993, the Cochrane Library, and SPORTDiscus, and then identified citations from papers retrieved and contacted experts in the field. Meta-analysis was limited to randomized trials or cohort studies for interventions that included stretching. Studies were excluded that lacked controls, in which stretching could not be assessed independently, or where studies did not include subjects in sporting or fitness activities. All articles were screened initially by one author. Six of 361 identified articles compared stretching with other methods to prevent injury. Data were abstracted by one author and then reviewed independently by three others. Data quality was assessed independently by three authors using a previously standardized instrument, and reviewers met to reconcile substantive differences in interpretation. We calculated weighted pooled odds ratios based on an intention-to-treat analysis as well as subgroup analyses by quality score and study design. Results: Stretching was not significantly associated with a reduction in total injuries (OR ϭ 0.93, CI 0.78 -1.11) and similar findings were seen in the subgroup analyses. Conclusion: There is not sufficient evidence to endorse or discontinue routine stretching before or after exercise to prevent injury among competitive or recreational athletes. Further research, especially well-conducted randomized controlled trials, is urgently needed to determine the proper role of stretching in sports. Key Words: ATHLETES, CONDITIONING, META-ANALYSIS, SYNTHESIS S tretching before participation in athletic activities is standard practice for all levels of sports, competitive or recreational. Athletes, coaches, trainers, physiotherapists, and physicians recommend stretching in an effort to both prevent injury and enhance performance; numerous journal articles and textbooks are devoted to the topic, providing a variety of approaches directed to different parts of the body and for specific sporting activities (1). As more people participate in sports and other recreational activities through social changes (e.g., Title IX) and increased recognition that physical activity is part of a healthy lifestyle, injury prevention becomes more important. However, some investigators have questioned the routine practice of stretching and contend that there is little evidence that stretching pre-or postparticipation prevents injury and that it might affect performance negatively We developed a logic model to illustrate the relations among stretching, flexibility, performance, and injury (Fig

The Complete Genome Sequence of ‘Candidatus Liberibacter solanacearum’, the Bacterium Associated with Potato Zebra Chip Disease

Zebra Chip (ZC) is an emerging plant disease that causes aboveground decline of potato shoots and generally results in unusable tubers. This disease has led to multi-million dollar losses for growers in the central and western United States over the past decade and impacts the livelihood of potato farmers in Mexico and New Zealand. ZC is associated with ‘Candidatus Liberibacter solanacearum’, a fastidious alpha-proteobacterium that is transmitted by a phloem-feeding psyllid vector, Bactericera cockerelli Sulc. Research on this disease has been hampered by a lack of robust culture methods and paucity of genome sequence information for ‘Ca. L. solanacearum’. Here we present the sequence of the 1.26 Mbp metagenome of ‘Ca. L. solanacearum’, based on DNA isolated from potato psyllids. The coding inventory of the ‘Ca. L. solanacearum’ genome was analyzed and compared to related Rhizobiaceae to better understand ‘Ca. L. solanacearum’ physiology and identify potential targets to develop improved treatment strategies. This analysis revealed a number of unique transporters and pathways, all potentially contributing to ZC pathogenesis. Some of these factors may have been acquired through horizontal gene transfer. Taxonomically, ‘Ca. L. solanacearum’ is related to ‘Ca. L. asiaticus’, a suspected causative agent of citrus huanglongbing, yet many genome rearrangements and several gene gains/losses are evident when comparing these two Liberibacter. species. Relative to ‘Ca. L. asiaticus’, ‘Ca. L. solanacearum’ probably has reduced capacity for nucleic acid modification, increased amino acid and vitamin biosynthesis functionalities, and gained a high-affinity iron transport system characteristic of several pathogenic microbes

Pathogenicity of fibroblast- and lymphocyte-specific variants of minute virus of mice.

We tested two strains of the minute virus of mice (MVM) for pathogenic effects and patterns of infection in laboratory mice. The two strains differ in their ability to infect differentiated cultured cells: the prototype virus, MVMp, infects only fibroblasts, while its variant, MVMi, is restricted to lymphocytes. We find that neither strain has any demonstrable effects on the T-cell function of mice infected as adults. In contrast, MVMi, but not MVMp, is able to induce a runting syndrome accompanied by mild immune deficiencies upon the infection of newborn mice. After neonatal infection, MVMi spreads to many organs, and the presence of viral replicative form DNA is evident in nucleic acid hybridization experiments. In contrast, replication of MVMp can be detected only by the seroconversion of infected animals. Newborn mice that grow abnormally as a result of MVMi infection also have low circulating antibody titers to the virus. This phenomenon may be a consequence of the lymphotropism of MVMi

Environmental measures of physical activity supports: Perception versus reality

Background Perceptions of the environment and physical activity have been associated using survey methods, yet little is known about the validity of environmental surveys. In this study, perceptions of the environment at neighborhood and community levels were assessed (1) to determine validity by comparing respondent perceptions to objective measures and (2) to determine test–retest reliability of the survey. Methods A telephone survey was administered to a stratified sample of Sumter County, South Carolina adults. Respondents’ home addresses were mapped using a geographic information system (GIS) (n =1112). As an indicator of validity, kappa statistics were used to measure agreement between perceptions and objective measures identified at neighborhood and community levels using GIS. A second survey in an independent sample (n=408) assessed test–retest reliability. Results When assessing perceptions of environmental and physical activity in a defined geographic area, validity and reliability for neighborhood survey items were κ=−0.02 to 0.37 and RHO=0.42 to 0.74, and for community survey items were κ=−0.07 to 0.25 and RHO=0.28 to 0.56. Conclusions Although causality between perception of access and safety and actual physical activity level cannot be assumed, those meeting national physical activity guidelines or reporting some physical activity demonstrated greatest agreement with access to recreation facilities, while those not meeting the guidelines demonstrated greater agreement with safety of recreation facilities. Factors such as distance and behavior may explain differences in perceptions at neighborhood and community levels. Using local environments with short distances in survey methods improves validity and reliability of results