首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
BackgroundPhysical activity (PA) may have an impact on digestive-system cancer (DSC) by improving insulin sensitivity and anticancer immune function and by reducing the exposure of the digestive tract to carcinogens by stimulating gastrointestinal motility, thus reducing transit time. The current study aimed to determine the effect of PA on different types of DSC via a systematic review and meta-analysis.MethodsIn accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched for relevant studies in PubMed, Embase, Web of Science, Cochrane Library, and China National Knowledge Infrastructure. Using a random effects model, the relationship between PA and different types of DSC was analyzed.ResultsThe data used for meta-analysis were derived from 161 risk estimates in 47 studies involving 5,797,768 participants and 55,162 cases. We assessed the pooled associations between high vs. low PA levels and the risk of DSC (risk ratio (RR)  = 0.82, 95% confidence interval (95%CI): 0.79–0.85), colon cancer (RR = 0.81, 95%CI: 0.76–0.87), rectal cancer (RR = 0.88, 95%CI: 0.80–0.98), colorectal cancer (RR = 0.77, 95%CI: 0.69–0.85), gallbladder cancer (RR = 0.79, 95%CI: 0.64–0.98), gastric cancer (RR = 0.83, 95%CI: 0.76–0.91), liver cancer (RR = 0.73, 0.60–0.89), oropharyngeal cancer (RR = 0.79, 95%CI: 0.72–0.87), and pancreatic cancer (RR = 0.85, 95%CI: 0.78–0.93). The findings were comparable between case-control studies (RR = 0.73, 95%CI: 0.68–0.78) and prospective cohort studies (RR = 0.88, 95%CI: 0.80–0.91). The meta-analysis of 9 studies reporting low, moderate, and high PA levels, with 17 risk estimates, showed that compared to low PA, moderate PA may also reduce the risk of DSC (RR = 0.89, 95%CI: 0.80–1.00), while compared to moderate PA, high PA seemed to slightly increase the risk of DSC, although the results were not statistically significant (RR = 1.11, 95%CI: 0.94–1.32). In addition, limited evidence from 5 studies suggested that meeting the international PA guidelines might not significantly reduce the risk of DSC (RR = 0.96, 95%CI: 0.91–1.02).ConclusionCompared to previous research, this systematic review has provided more comprehensive information about the inverse relationship between PA and DSC risk. The updated evidence from the current meta-analysis indicates that a moderate-to-high PA level is a common protective factor that can significantly lower the overall risk of DSC. However, the reduction rate for specific cancers may vary. In addition, limited evidence suggests that meeting the international PA guidelines might not significantly reduce the risk of DSC. Thus, future studies must be conducted to determine the optimal dosage, frequency, intensity, and duration of PA required to reduce DSC risk effectively.  相似文献   

2.
This article aims to provide an overview of the current state of research on the relationship between loneliness and physical activity (PA). A systematic literature search was conducted to identify all empirical studies assessing this relationship. A total of 37 studies stemming from 36 publications met the inclusion criteria. Study analyses comprised an individual consideration of each study and a systematic summarization of the studies. The majority of eligible studies focused on adolescent or elderly populations. Direct negative associations between PA and loneliness were found in half of the 24 cross-sectional studies. Of the seven identified longitudinal studies, one found a direct negative influence of PA on loneliness. Four longitudinal studies found evidence for a reverse influence, namely of loneliness on PA. Five intervention studies found PA to reduce loneliness. Two of the cross-sectional studies and one of the intervention studies found social support and social competence to moderate or to mediate the relationship between PA and loneliness. The findings indicate that PA can contribute to a decrease in loneliness. However, studies also indicate that any beneficial effect is dependent upon the quality of relationships present during physical activity. Additionally, loneliness itself might reduce the probability of being physically active.  相似文献   

3.
The purpose of this systematic review and meta-analysis was to gather, catalogue, assess, and evaluate the available evidence examining implicit beliefs about ability in the sport, physical activity, and physical education contexts. A total of 43 studies were found, of which 39 were subjected to meta analyses. With only 7 experimental studies, the strength of evidence is moderate, and the field would benefit from greater experimental work. Overall, incremental beliefs were moderately associated with a small group of theoretically derived correlates, while entity beliefs were only weakly associated. The field would benefit from expanding these outcomes to include a wider range of pertinent outcomes. Researchers should focus their efforts on systematically exploring the most powerful ways of inducing adaptive implicit beliefs with the aim of providing solutions to significant problems such as preventing dropout from organised sports, improving academic grades in and beyond physical education, and increasing levels of physical activity.  相似文献   

4.
BackgroundPhysical activity (PA) in the early years is associated with a range of positive health outcomes. Fundamental motor skill (FMS) competence is associated with PA and is theorized to be driven by PA in the early years and vice versa in mid to late childhood. However, to date, no studies have meta-analyzed the association between PA and FMS in the early years.MethodsSix electronic databases were searched for articles published up to April 2019. Cross-sectional and longitudinal studies were included if they targeted children (ages 3–6 year) as the population of the study and assessed the association between objectively measured PA and FMS. Total FMS, total physical activity (TPA), and moderate-to-vigorous physical activity (MVPA) data were meta-analyzed using a random effects model.ResultsWe identified 24,815 titles and abstracts. In total, 19 studies met the inclusion criteria, including 14 cross-sectional and 4 longitudinal studies, as well as 1 study with cross-sectional and longitudinal analysis. There was a significant but small positive association between FMS and MVPA (r = 0.20, 95% confidence interval (CI): 0.13–0.26) and TPA (r = 0.20, 95%CI: 0.12–0.28). Findings from longitudinal studies revealed that PA drives FMS in early childhood. Mediation was explored in 1 study, which found that perceived motor competence did not mediate the association between FMS and PA.ConclusionUsing a meta-analysis, this study is the first to show a positive association between FMS, MVPA, and TPA in the early years of childhood, suggesting that the association begins at an early age. Limited evidence from longitudinal studies supports the theory that PA drives FMS in the early years of childhood. More evidence is needed from large studies to track PA and FMS until mid to late childhood and to explore the mediators of this association.  相似文献   

5.
Siblings are important developmental agents, yet understanding of their influence in physical activity settings is limited. Prior to developing sibling-focused research questions, a comprehensive summary of the diverse literature regarding siblings in the physical domain is needed. A systematic review of siblings in physical activity contexts was conducted to gauge current knowledge on this topic and provide a guide for future empirical endeavors. A comprehensive literature search of CINAHL, The Cochrane Library, PsychINFO, PubMed, SPORTDiscus, and Web of Science yielded 68 studies spanning 46 years (1970–2016). The results showed siblings to be actively and passively associated with physical activity levels and to be sources of both positive and negative experiences in sport. The sex composition of sibling dyads appears to moderate outcomes. Overall, the findings provide an outline of sibling-based subject areas, identify topics needing further attention, and showcase methods with potential to advance the study of sibling relationships in the physical domain.  相似文献   

6.
BackgroundDespite the well-established health benefits of physical activity (PA) for young people (aged 4–19 years), most do not meet PA guidelines. Policies that support PA in schools may be promising, but their impact on PA behavior is poorly understood. The aim of this systematic review was to ascertain the level and type of evidence reported in the international scientific literature for policies within the school setting that contribute directly or indirectly to increasing PA.MethodsThis systematic review is compliant with Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Six databases were searched using key concepts of policy, school, evaluation, and PA. Following title and abstract screening of 2323 studies, 25 progressed to data synthesis. Methodological quality was assessed using standardized tools, and the strength of the evidence of policy impact was described based on pre-determined codes: positive, negative, inconclusive, or untested statistically.ResultsEvidence emerged for 9 policy areas that had a direct or indirect effect on PA within the school setting. These were whole school PA policy, physical education, sport/extracurricular PA, classroom-based PA, active breaks/recess, physical environment, shared use agreements, active school transport, and surveillance. The bulk of the evidence was significantly positive (54%), 27% was inconclusive, 9% was significantly negative, and 11% was untested (due to rounding, some numbers add to 99% or 101%). Frequency of evidence was highest in the primary setting (41%), 34% in the secondary setting, and 24% in primary/secondary combined school settings. By policy area, frequency of evidence was highest for sport/extracurricular PA (35%), 17% for physical education, and 12% for whole school PA policy, with evidence for shared use agreements between schools and local communities rarely reported (2%). Comparing relative strength of evidence, the evidence for shared use agreements, though sparse, was 100% positive, while 60% of the evidence for whole school PA policy, 59% of the evidence for sport/extracurricular PA, 57% of the evidence for physical education, 50% of the evidence for PA in classroom, and 50% of the evidence for active breaks/recess were positive.ConclusionThe current evidence base supports the effectiveness of PA policy actions within the school setting but cautions against a “one-size-fits-all” approach and emphasizes the need to examine policy implementation to maximize translation into practice. Greater clarity regarding terminology, measurement, and methods for evaluation of policy interventions is needed.  相似文献   

7.
BackgroundThis study systematically synthesized and quantified the relationship linking state laws governing school physical education (PE) to PE attendance and physical activity (PA) in class and throughout the day and week among students in the USA.MethodsA keyword search was performed in PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Academic Search Complete, and EconLit. Meta-analyses were performed to estimate the effects of state PE laws.ResultsA total of 17 studies were included in the review, and five contributed to the meta-analyses. A total of 8 studies used nationally representative school- or student-level data, three focused on multiple states, and the remaining six examined the PE laws of a single state. The presence and strength of state PE laws were positively associated with PE attendance and the frequency and duration of PA during PE classes and throughout the school day. Compared to those residing in states with weak or no PE laws, students in states with strong PE laws had an additional 0.2 days (95% confidence interval (95%CI): 0.1–0.4) of PE attendance per week and spent an additional 33.9 min (95%CI: 22.7–45.0) participating PE classes per week. State PE laws affected girls’ PA more than boys’. Different aspects of state PE laws tended to affect students’ PE attendance differently. Disparities in the implementation of state PE laws existed across schools.ConclusionFuture studies should adopt objective measures on PE and PA participation and examine the roles schools and districts play in mediating the effect of state PE laws on students’ PE attendance and PA.  相似文献   

8.
PurposeThe aim of this mixed-studies systematic review was to ascertain the effectiveness of school-based interventions in increasing physical activity (PA) and/or reducing sedentary time (ST) in children aged 5–11 years, as well as to explore their effectiveness in relation to categories of the theory of expanded, extended, and enhanced opportunity (TEO).MethodsAdhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 5 databases were searched using predefined search terms. Following title and abstract screening of 1115 records, the removal of duplicates (n = 584) and articles that did not meet the inclusion criteria agreed to a priori (n = 419) resulted in 112 records that were full-text screened. Two independent reviewers subsequently used the mixed-methods appraisal tool to assess the methodological quality of 57 full-text studies that met the inclusion criteria after full-text screening. The interventions were summarised using the TIDierR checklist and TEO. The strength of evidence was determined using a 5-level rating system utilising a published decision tree.ResultsOverall evidence ratings for interventions implemented within school settings were: no evidence of effects on moderate-to-vigorous physical activity (MVPA) and inconclusive evidence of effects on sedentary time. In relation to the TEO, expansion of PA appeared to be the most promising intervention type for MVPA, with moderate evidence of effect, whereas extension and enhancement of PA opportunity demonstrated no evidence of effect. A critical issue of possible compensatory behavior was identified by analysis of intervention effect in relation to PA measurement duration; when studies measured changes in PA during the actual intervention, there was moderate evidence of effect, whereas those that measured changes in PA during the school day presented inconclusive evidence of effect, and those that measured changes in PA over a whole day yielded no evidence of effect. Two meta-analyses of those studies using a whole-day accelerometer measure for MVPA or ST showed a significant but moderate effect for MVPA (effect size = 0.51; 95% confidence interval (CI): 0.02–0.99) and a large but nonsignificant effect for ST (effect size = 1.15; 95%CI: –1.03 to 3.33); both meta-analyses demonstrated low precision, considerable inconsistency, and high heterogeneity.ConclusionThe findings have important implications for future intervention research in terms of intervention design, implementation, and evaluation.  相似文献   

9.
Background:One of the pathological hallmarks distinguishing Alzheimer’s disease from other dementias is the accumulation of amyloid beta(Aβ).Higher physical activity is associated with decreased dementia risk,and one potential path could be through Aβ levels modulation.We aimed to explore the relationship between physical activity and Aβ in middle-aged and older adults.Methods:A systematic search of PubMed,Web of Science,PsycINFO,Cochrane Central Register of Controlled Trials,and SPORTDiscus was...  相似文献   

10.
ABSTRACT

The aim of this study was to systematically review the literature to verify the association between participation in sports (PS) in childhood and adolescence and physical activity (PA) in adulthood. A systematic search was conducted in the following databases: Medline (PUBMED), Web of Science, Scopus, and SPORTDiscus, LILACS and SciELO. All steps of the process followed the recommendations of the PRISMA FlowDiagram. After all the steps of the process, 29 articles were included for analysis. In general, only three of the studies analyzed found no relation between PS in childhood and adolescence and PA in adulthood. However, a positive relationship was found to be weak in only 7% of the studies, a moderate relation in 62% of the studies, and a strong relation in 21%. It was found that higher weekly frequencies of PS; persistence of at least three years of PS and, finally, the highest level of practice and/or competition reached were related to higher levels of PA in adulthood. Thus, it can be concluded that there is a positive association considered moderate to strong between PS in childhood and adolescence and PA in adulthood.  相似文献   

11.
It is common knowledge that physical activity leads to numerous health and psychological benefits. However; the relationship between children's physical activity and academic achievement has been debated in the literature. Some studies have found strong, positive relationships between physical activity and cognitive outcomes, while other studies have reported small, negative associations. This study was a comprehensive, quantitative synthesis of the literature, using a total of 59 studies from 1947 to 2009 for analysis. Results indicated a significant and positive effect of physical activity on children's achievement and cognitive outcomes, with aerobic exercise having the greatest effect. A number of moderator variables were also found to play a significant role in this relationship. Findings are discussed in light of improving children's academic performance and changing school-based policy.  相似文献   

12.
Sports mega-events, such as the Olympic and Paralympic Games, have the potential to inspire increases in population physical activity, yet investigations concerning such legacy outcomes have been inconclusive. This may be due to research design limitations or inconsistent leveraging of potential hosting benefits by event organizers. This systematic review aims to identify current knowledge about the capacity of sports mega-events to inspire increases in physical activity participation among adult populations and develop a research agenda to guide future legacy evaluations. Peer-reviewed, English-language studies published on or after the year 2000 were considered. Six academic databases and grey literature sources were searched, and articles were assessed for methodological quality. Reporting followed PRISMA conventions for systematic reviews. Nine studies were selected after quality evaluation, including previous reviews, quantitative and qualitative research. Most studies found no evidence for long-term physical activity outcomes associated with hosting sports mega-events, although limitations and gaps were identified. These included lack of longitudinal or cohort studies, limited differentiation of subpopulations, use of non-validated instruments, and lack of triangulation for qualitative findings. Only one cohort study from Japan identified sustainable and significant physical activity increases resulting from a previous sports mega-event. Considering theory, the commonly cited Demonstration Effect was reportedly an unreliable framework, although the Festival Effect and Social Ecological Model appear more promising for anticipating and explaining legacy effects. With less than two years until the Tokyo 2020 Olympiad, it is appropriate to commence high-quality legacy research drawing on lessons learned from previous studies.  相似文献   

13.
To increase young people's physical activity (PA) levels it is important to understand the correlates of PA in children and adolescents. We sought to identify factors associated with children's and adolescents’ PA by reviewing systematic quantitative reviews of non-intervention research. Systematic reviews examining associations between quantitatively measured variables and PA in young people (< 19 years) from 2000–2010 were identified using electronic and manual searches. Nine systematic reviews were identified. Demographic/biological correlates of PA were age and gender. Psychological correlates of PA were positive motivation, positive body image and the existence of barriers to PA. Behavioural correlates of PA were previous PA, sport participation, smoking, and sedentary behaviour. Social/cultural correlates of PA were parental influence and social support, and environmental correlates of PA were access to facilities, distance from home to school, time spent outside, and local crime. The evidence is suggestive of a number of different types of correlates of PA for children and adolescents. Beyond age and gender, though, most are likely to have only small or small-to-moderate effects in isolation and may work best in interaction with other influences. Psychologists must look to social, organisational and community-level correlates in addition to individual correlates.  相似文献   

14.
ABSTRACT

This study aims to quantify the association between aerobic fitness and academic achievement, and determine how different aerobic fitness tests and individual demographic characteristics may modify this association. It includes 41 cross-sectional and 7 longitudinal studies focusing on children and adolescents, from MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database and Web of Science. Pooled effect sizes (ES) were estimated for the association between aerobic fitness and specific domains of academic achievement. Subgroup analyses and meta-regressions were based on aerobic fitness tests and demographic characteristics. The ES for the association between aerobic fitness with language/reading-skills, mathematics-related skills and composite scores, were 0.23 (95% CI: 0.12; 0.34); 0.27 (95% CI: 0.19; 0.36) and 0.28 (95% CI: 0.12; 0.45), respectively. Subgroup analyses by aerobic fitness test modified these associations; additionally, analyses by sex or age showed differences between boys and girls as well as between children and adolescents. Finally, meta-regressions revealed a slight effect of body mass index on these associations. Cardiorespiratory fitness is positively associated with academic achievement. Associations were dependent on demographic and aerobic fitness test characteristics, being stronger in boys than in girls, and in children than in adolescents.

Systematic review registration: PROSPERO CRD42017069677  相似文献   

15.
Continued advancement in the field of physical activity and health promotion relies heavily on the synthesis of rigorous scientific evidence. As such, systematic reviews and meta-analyses of randomized controlled trials have led to a better understanding of which intervention strategies are superior (i.e., produce the greatest effects) in physical activity-based health behavior change interventions. Indeed, standard meta-analytic approaches have allowed researchers in the field to synthesize relevant experimental evidence using pairwise procedures that produce reliable estimates of the homogeneity, magnitude, and potential biases in the observed effects. However, pairwise meta-analytic procedures are only capable to discerning differences in effects between a select intervention strategy and a select comparison or control condition. In order to maximize the impact of physical activity interventions on health-related outcomes, it is necessary to establish evidence concerning the comparative efficacy of all relevant physical activity intervention strategies. The development of network meta-analysis (NMA)—most commonly used in medical-based clinical trials—has allowed for the quantification of indirect comparisons, even in the absence of direct, head-to-head trials. Thus, it stands to reason that NMA can be applied in physical activity and health promotion research to identify the best intervention strategies. Given that this analysis technique is novel and largely unexplored in the field of physical activity and health promotion, care must be taken in its application to ensure reliable estimates and discernment of the effect sizes among interventions. Therefore, the purpose of this review is to comment on the potential application and importance of NMA in the field of physical activity and health promotion, describe how to properly and effectively apply this technique, and suggest important considerations for its appropriate application in this field. In this paper, overviews of the foundations of NMA and commonly used approaches for conducting NMA are provided, followed by assumptions related to NMA, opportunities and challenges in NMA, and a step-by-step example of developing and conducting an NMA.  相似文献   

16.
Purpose:The study aimed to conduct a comprehensive systematic review and meta-analysis of injury incidence in professional skiers and snowboarders.Methods:We systematically searched PubMed,Web of Science,and MEDLINE for studies on injury incidence published from inception to April 2020.Injury data were extracted,alongside information on injury location,severity,type,cause,and sport discipline.Incidence of injuries was presented per 1000 athlete-days,with 95%confidence intervals(95%CIs).Results:The search identified 462 articles,and 22 were included in our review.The overall incidence of injuries among professional skiers and snowboarders was 3.49 per 1000 athlete-days(95%CI:2.97-4.01).Lower extremity had the highest injury incidence(1.54 per 1000 athletedays,95%CI:1.24-1.84).Incidence rates of slight,mild,moderate,and severe injuries were 0.26,0.31,0.57,and 0.59 per 1000 athlete-days,respectively.Contusion had the highest incidence rate(1.82 per 1000 athlete-days,95%CI:1.01-2.63).The most common cause of injury was contact trauma(3.20 per 1000 athlete-days,95%CI:1.32-5.08).Freestyle skiing had the highest incidence rate(6.83 per 1000 athlete-days,95%CI:4.00-9.66),and Nordic skiing had the lowest rate(2.70 per 1000 athlete-days,95%CI:1.94-3.46).Conclusion:Professional skiers and snowboarders have a substantial risk of sustaining injuries.Our findings can be used to inform the planning and provision of healthcare for elite participants in different snow sports.  相似文献   

17.
This study examined the effects of utilizing a wearable activity tracker in a credit-based physical activity instructional program (PAIP) for promoting physical activity (PA) in college students. Fourteen PAIP courses in a large public university were randomly assigned into intervention (k = 7; n = 101) and control (k = 7; n = 86) groups. All courses focused on a core curriculum that covers basic exercise and behavioral science contents through lectures and activity sessions. A Misfit Flash activity tracker was provided to students in the intervention group. Objective PA assessments occurred at baseline, mid-, and end-of-semester during a 15-week academic semester. The control group showed a significant reduction in moderate- and vigorous-intensity PA (MVPA) minutes from baseline to the end-of-semester (<.05), whereas the intervention group showed no changes in MVPA minutes over time. However, the intervention group also showed increased sedentary time and decreased time spent in light-intensity PA during the intervention period. Taken together, the present study found null effects of utilizing the wearable activity tracker in promoting PA in college students suggesting that intervention of primary using the wearable activity tracker as a behavior change strategy may not be effective to increase in PA in this setting.  相似文献   

18.
This meta-analysis aims to determine the effects of regular swimming on bone mineral density (BMD) in young adults (18–30 years). A systematic search was performed in Pubmed, SPORTDiscus and the Cochrane Library from the earliest possible year to March 2016. Swimmers were compared to non-athletic controls (CG) and to high-impact athletes (HIGH). Effect sizes with the Hedges g in random effects models were developed. Fourteen studies met the inclusion criteria and were included in the meta-analyses. Swimmers presented similar BMD values to CG in whole-body (g = ?0.20; P = 0.251), femoral neck (g = ?0.05; P = 0.818) and lumbar spine (g = 0.18; P = 0.492); and lower BMD in the whole-body (g = ?1.21; P < 0.001), femoral neck (g = ?1.51; P < 0.001) and lumbar spine (g = ?0.84; P = 0.017) than the HIGH. For the whole-body differences, the higher the latitude the smaller the differences between swimmers and HIGH (B = 0.10; P = 0.001). For the femoral neck differences, age also seemed to reduce the differences between groups (B = 0.19; P = 0.020). Young adult swimmers present similar BMD values than CG and lower values than HIGH.  相似文献   

19.
20.
ABSTRACT

Interval exercise training is increasingly recommended to improve health and fitness; however, it is not known if cardiovascular risk is different from continuous exercise protocols. This systematic review with meta-analyses assessed the effect of a single bout of interval exercise on cardiovascular responses that indicate risk of cardiac fibrillation and infarction compared to continuous exercise. Electronic databases Medline, CINAHL, Embase, Scopus and Cochrane were searched. Key inclusion criteria were: (1) intervals of the same intensity and duration followed by a recovery period and (2) reporting at least one of blood pressure, heart rate variability, arterial stiffness or function. Cochrane Risk of Bias tool and GRADE approach were used. Meta-analyses found that systolic blood pressure responses to interval exercise did not differ from responses to continuous exercise immediately (MD 8 mmHg [95% CI ?32, 47], p = 0.71) or at 60 min following exercise (MD 0 mmHg [95% CI ?2, 1], p = 0.79). However, reductions in diastolic blood pressure and flow-mediated dilation with interval exercise were observed 10–15 min post-exercise. The available evidence indicates that interval exercise does not convey higher cardiovascular risk than continuous exercise. Further investigation is required to establish the safety of interval exercise for clinical populations.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号