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Background: Creatine is the most widely used supplementation to increase performance in strength; however, the most recent meta-analysis focused specifically on supplementation responses in muscles of the lower limbs without regard to upper limbs. Objective: We aimed to systematically review the effect of creatine supplementation on upper limb strength performance. Methods: We conducted a systematic review and meta-analyses of all randomized controlled trials comparing creatine supplementation with a placebo, with strength performance measured in exercises shorter than 3 min in duration. The search strategy used the keywords 'creatine', 'supplementation', and 'performance'. Independent variables were age, sex and level of physical activity at baseline, while dependent variables were creatine loading, total dose, duration, time interval between baseline (T0) and the end of the supplementation (T1), and any training during supplementation. We conducted three meta-analyses: at T0 and T1, and on changes between T0 and T1. Each meta-analysis was stratified within upper limb muscle groups. Results: We included 53 studies (563 individuals in the creatine supplementation group and 575 controls). Results did not differ at T0, while, at T1, the effect size (ES) for bench press and chest press were 0.265 (95 % CI 0.132-0.398; p < 0.001) and 0.677 (95 % CI 0.149-1.206; p = 0.012), respectively. Overall, pectoral ES was 0.289 (95 % CI 0.160-0.419; p = 0.000), and global upper limb ES was 0.317 (95 % CI 0.185-0.449; p < 0.001). Meta-analysis of changes between T0 and T1 gave similar results. The meta-regression showed no link with characteristics of population or supplementation, demonstrating the efficacy of creatine independently of all listed conditions. Conclusion: Creatine supplementation is effective in upper limb strength performance for exercise with a duration of less than 3 min, independent of population characteristics, training protocols, and supplementary doses or duration. [ABSTRACT FROM AUTHOR]

Background: Creatine is the most widely used supplementation to increase strength performance. However, the few meta-analyses are more than 10 years old and suffer from inclusion bias such as the absence of randomization and placebo, the diversity of the inclusion criteria (aerobic/endurance, anaerobic/strength), no evaluation on specific muscles or group of muscles, and the considerable amount of conflicting results within the last decade. Objective: The objective of this systematic review was to evaluate meta-analyzed effects of creatine supplementation on lower limb strength performance. Methods: We conducted a systematic review and meta-analyses of all randomized controlled trials comparing creatine supplementation with a placebo, with strength performance of the lower limbs measured in exercises lasting less than 3 min. The search strategy used the keywords 'creatine supplementation' and 'performance'. Dependent variables were creatine loading, total dose, duration, the time-intervals between baseline (T0) and the end of the supplementation (T1), as well as any training during supplementation. Independent variables were age, sex, and level of physical activity at baseline. We conducted meta-analyses at T1, and on changes between T0 and T1. Each meta-analysis was stratified within lower limb muscle groups and exercise tests. Results: We included 60 studies (646 individuals in the creatine supplementation group and 651 controls). At T1, the effect size (ES) among stratification for squat and leg press were, respectively, 0.336 (95 % CI 0.047-0.625, p = 0.023) and 0.297 (95 % CI 0.098-0.496, p = 0.003). Overall quadriceps ES was 0.266 (95 % CI 0.150-0.381, p < 0.001). Global lower limb ES was 0.235 (95 % CI 0.125-0.346, p < 0.001). Meta-analysis on changes between T0 and T1 gave similar results. The meta-regression showed no links with characteristics of population or of supplementation, demonstrating the creatine efficacy effects, independent of all listed conditions. Conclusion: Creatine supplementation is effective in lower limb strength performance for exercise with a duration of less than 3 min, independent of population characteristic, training protocols, and supplementary doses and duration. [ABSTRACT FROM AUTHOR]

Objective We aimed to evaluate the place of lumbar support in the management of nonspecific low back pain. Material and methods We conducted a systematic review with the following databases: Pubmed, Cochrane Library, Science Direct and Pedro. The search strategy used the keywords low back pain; lumbar orthosis; lumbar belt; back support; lumbar support; lumbar brace. To be included, studies needed to have one or more keywords selected. The search was limited to French and English articles. The major exclusion criterion was studies included rigid orthotics of the trunk. High Authority of health statement was used to check the quality of reporting. Data were also analyzed according to stages of the disease (acute, subacute, and chronic) and in prevention (primary and secondary). Results We included 28 studies. Quality assessment was heterogeneous. The systematic review showed no official recommendations for lumbar support prescription among the general population. Lumbar support was effective on function, pain, and relative time intervals for dispensing medication with subacute low back pain. It was also effective with probability of low back pain recurrence in secondary prevention. Orthosis’ benefits were not highlighted probably due to the lack of observance, which was a limiting factor. It is a bias because observance was not systematically studied in the literature. To our knowledge, there is no meta-analysis because evaluation criteria are heterogeneous. Discussion/Conclusion To date, there is no proof to prescribe lumbar support in the management of low back pain general population. An individual prescription would be discussed for subacute low back pain or in secondary prevention. Further studies with a higher quality assessment are necessary in order to identify phenotypes of patients’ responders to lumbar support. The function would be preferred as a main assessment criterion. [ABSTRACT FROM AUTHOR]