Exercise is medicine, for the body and the brain Nutritional Intervention as a Preventive Approach for Cognitive-Related Outcomes in Cognitively Healthy Older Adults: A Systematic Review. What are the most effective behaviour change techniques to promote physical activity and/or reduce sedentary behaviour in inactive adults? A systematic review protocol Changing everyday memory behaviour in amnestic mild cognitive impairment: A randomised controlled trial A randomised control trial of the cognitive effects of working in a seated as opposed to a standing position in office workers Energy balance-related behaviours associated with overweight and obesity in preschool children: a systematic review of prospective studies. Examining the theory‐effectiveness hypothesis: A systematic review of systematic reviews Higher levels of objectively measured sedentary behavior is associated with worse cognitive ability: Two-year follow-up study in community-dwelling older adults Impact of aerobic exercise on neurobehavioral outcomes. A complex multimodal activity intervention to reduce the risk of dementia in mild cognitive impairment–ThinkingFit: pilot and feasibility study for a randomized controlled trial
Cognitive decline is one of the most pressing healthcare issues of the 21st century . Worldwide , one new case of major cognitive decline ( ie , dementia ) is detected every 4 s.1 Given that no effective pharmacological treatment to alter the progress of cognitive decline exists , there is much interest in lifestyle approaches for preventing or treating dementia . Ideally , such strategies should be cost-efficient and widely accessible at a societal level to have the largest benefit for older adults with varying income and functional status levels . One attractive solution that aligns with the above criteria is exercise . However , despite a large and consistent pool of evidence generated over the past five decades linking exercise to improved cognitive functions in older adults,2 there is a reluctance among academics , healthcare practitioners and the public alike to embrace exercise as a prevention and treatment strategy for cognitive decline . For example , the National Institutes of Health ( NIH ) consensus statement from 20103 concedes that there appears to be preliminary data to support the efficacy of exercise in improving cognitive function . However , they caution that there is currently no strong evidence to suggest that modifiable lifestyle factors can alter the trajectory of cognitive decline . Adding fuel to the fire are publications such as a 2013 systematic review of r and omised controlled trials ( RCTs ) ( prior to 31 October 2011 ) reporting ‘ weak ’ evidence for the effects of exercise on cognition.4 We must highlight that the search strategy used in that systematic review failed to capture many pertinent papers providing evidence from RCTs that exercise  promotes cognitive and brain plasticity not only in healthy older adults but also in those with cognitive impairment . Furthermore , there are a number of animal studies that provide insight into the molecular and cellular mechanisms by which exercise  promotes neuroplasticity.5 In a previous commentary , The link diet-cognitive function/dementia has been largely investigated in observational studies ; however , there was a lack of evidence from r and omized clinical trials ( RCTs ) on the prevention of late-life cognitive disorders though dietary intervention in cognitively healthy older adults . In the present article , we systematic ally review ed RCTs published in the last four years ( 2014 - 2017 ) exploring nutritional intervention efficacy in preventing the onset of late-life cognitive disorders and dementia in cognitively healthy subjects aged 60 years and older using different levels of investigation ( i.e. , dietary pattern changes/medical food/nutraceutical supplementation/multidomain approach and dietary macro- and micronutrient approaches ) as well as possible underlying mechanisms of nutritional prevention . From the 35 included RCTs , there was moderate evidence that intervention through dietary pattern changes , medical food/nutraceutical supplementation , and multidomain approach improved specific cognitive domains or cognitive-related blood biomarkers . There was high evidence that protein supplementation improved specific cognitive domains or functional status in prefrail older adults without effect on cognitive function . For fatty acid supplementation , mainly long-chain polyunsaturated fatty acids , there was emerging evidence suggesting an impact of this approach in improving specific cognitive domains , magnetic resonance imaging ( MRI ) findings , and /or cognitive-related biomarkers also in selected subgroups of older subjects , although some results were conflicting . There was convincing evidence of an impact of non-flavonoid polyphenol and flavonoid supplementations in improving specific cognitive domains and /or MRI findings . Finally , there was only low evidence suggesting efficacy of intervention with homocysteine-related and antioxidant vitamins in improving cognitive functions , dementia incidence , or cognitive-related biomarkers in cognitively healthy older subjects Introduction Large proportions of the population are not meeting recommended levels of physical activity and have increasingly sedentary lifestyles . Low levels of physical activity are predictive of poor health outcomes and time spent sedentary is related to a host of risk factors independently of physical activity levels . Building an evidence base of the best approaches to intervene in the lifestyles of inactive individuals is crucial in preventing long-term disease , disability and higher mortality rates . Methods and analysis Systematic search es will be conducted on all relevant data bases ( eg , PubMed , Scopus , CINAHL , PsycINFO ) . Studies will be included if they assess interventions aim ed at changing physical activity or sedentary behaviour levels in adults ( over 18 ) who are inactive and do not suffer from chronic conditions . Studies must also be r and omised controlled trials ( RCTs ) , have a primary outcome of physical activity or sedentary behaviour , and measure outcomes at least 6 months after intervention completion . Studies will be coded using the Behaviour Change Technique ( BCT ) taxonomy v1 and Template for Intervention Description and Replication ( TIDieR ) guidelines . 2 review ers will independently screen full-text articles and extract data on study characteristics , participants , BCTs , intervention features and outcome measures . Study quality will also be assessed independently by 2 review ers using the Cochrane risk of bias tool . A meta- analysis will be considered if there is sufficient homogeneity across outcomes . GRADE criteria will be used to assess quality of evidence . Dissemination This will be the first review to systematic ally appraise interventions aim ed at changing the physical activity or sedentary behaviour of inactive individuals using RCT design s with a 6-month follow-up post-intervention . This review will better inform intervention design ers targeting inactive population s and inform the design of a future complex intervention . Review registration number This protocol was registered with the International Prospect i ve Register of Systematic Review s ( PROSPERO ) on 17 October 2014 ( registration number : CRD42014014321 ) One of the defining differences between mild cognitive impairment ( MCI ) and dementia is the degree of independence in everyday activities . Effecting memory-related behavioural change in MCI could help maintain daily function and prolong the time before onset of dependency . However , it is well known that changing previously well-established behaviours is difficult to achieve . We conducted a r and omised controlled trial to evaluate the effectiveness of a multidisciplinary group-based intervention programme in changing everyday memory behaviour in individuals with amnestic MCI . The intervention provided evidence d-based memory training and lifestyle education to optimise memory behaviour .  Fifty-four participants were r and omly assigned to treatment or waitlist-control conditions . Consistent with our primary goal , treatment participants showed an increase in memory- strategy knowledge and use from pre-test to immediate post-test , and these gains were maintained at three-month post-test relative to waitlist controls . There were no group differences in memory beliefs or on laboratory tests of objective memory performance . The increase in memory- strategy knowledge and use was associated with the degree of participation in the programme . Individuals with MCI , therefore , can acquire and maintain knowledge about memory strategies and , importantly , can change their everyday memory behaviour by putting this knowledge into practice . This incorporation of practical memory strategies into daily routines could potentially provide the means for maintaining functional independence by individuals with MCI , an issue to be addressed in future research Abstract Sedentary behaviour is increasing and has been identified as a potential significant health risk , particularly for desk-based employees . The development of sit-st and workstations in the workplace is one approach to reduce sedentary behaviour . However , there is uncertainty about the effects of sit-st and workstations on cognitive functioning .  A sample of 36 university staff participated in a within-subjects r and omised control trial examining the effect of sitting vs. st and ing for one hour per day for five consecutive days on attention , information processing speed , short-term memory , working memory and task efficiency . The results of the study showed no statistically significant difference in cognitive performance or work efficiency between the sitting and st and ing conditions , with all effect sizes being small to very small ( all ds < .2 ) . This result suggests that the use of sit-st and workstations is not associated with a reduction in cognitive performance . Practitioner Summary : Although it has been reported that the use of sit-st and desks may help offset adverse health effects of prolonged sitting , there is scant evidence about changes in productivity . This r and omised control study showed that there was no difference between sitting and st and ing for one hour on cognitive function or task efficiency in university staff The current review aim ed to systematic ally identify dietary , physical activity and sedentary behaviours in preschool children ( 4 - 6 years of age ) that are prospect ively related to overweight or obesity later in childhood . Prospect i ve studies published between January 1990 and June 2010 were selected from search es in PubMed , EMBASE , PsycINFO , CINAHL and Cochrane Library . Studies examining the prospect i ve association between at least one relevant behaviour measured during preschool period ( children aged 4 - 6 years at baseline ) in relation to at least one anthropometric measurement at follow-up ( age < 18 years ) were included . Harvest plots were used to summarize the results and draw conclusions from the evidence . Of the 8,718 retrieved papers , 23 papers reporting on 15 different study sample s were included in this review . Strong evidence was found for an inverse association between total physical activity and overweight . Moderate evidence was observed for a positive association between television viewing and overweight . Because of the heterogeneity in the assessed dietary behaviours , insufficient evidence was found for an association between  dietary intake or specific dietary behaviours and overweight . These results suggest that interventions aim ing to prevent overweight among preschool children should focus on promotion of total physical activity and limitation of screen time and that further research is needed to establish whether and which dietary behaviours are important for obesity prevention in this age group . However , despite the lack of evidence for dietary behaviours from the present review , future interventions may already target specific dietary behaviours that are highly prevalent and for which there a clear rationale as well as preliminary evidence that these behaviours are associated with overweight PURPOSE Health interventions based on theory may be more effective than those that are not . This review of review s synthesizes all published r and omized controlled trial ( RCT ) meta-analytic evidence from the last decade to examine whether theory-based interventions were found to be associated with more effective  adult health behaviour change interventions . METHODS Systematic review s including meta-analyses were identified by search ing Medline , CINAHL , PsycINFO , and CDSR . A narrative synthesis was used to summarize and analyse the evidence . Only review s including RCTs of health behaviour change interventions with adults aged 18 + published from 2007 to 2017 were included . RESULTS Of 8,659 articles , nine systematic review s met inclusion criteria . The majority of review s ( n = 8) suggested no increased effectiveness for theory-based compared to non-theory-based interventions for effectiveness of outcomes relating to health behaviour . Less than half of the RCTs included in the review s reported the use of theory ( 85/183 ) . Two review s suggested interventions based on control theory , motivational interviewing , or self-determination theory were associated with greater effectiveness for physical activity and /or dietary interventions and outcomes . Method ological and reporting issues limit the conclusions . CONCLUSIONS Theory-based interventions as currently operationalized in systematic review s were not found to be more effective than non-theory-based interventions . Method ological and reporting issues at study and review level may not reflect the true utility of theory use within health behaviour interventions . The promotion of theory use may benefit from using a multifaceted argument , rather than a narrow focus of increased effectiveness . Statement of contribution What is already known on this subject ? Theory use is regularly promoted by cl aim ing that it will lead to more effective behaviour change interventions . Theory use has been frequently linked to effectiveness within systematic review s of behaviour change interventions . The theory-effectiveness hypothesis has not been systematic ally examined at the systematic review level . What does this study add ? Theory use as operationalized by systematic review authors was not associated with increased effectiveness within systematic review s examining r and omized controlled trials of behaviour change interventions in adults . Interventions based on control theory , motivational interviewing , or self-determination theory were associated with greater effectiveness for physical activity and /or dietary interventions and outcomes . Theory use should be promoted using a multifaceted argument , and assertions for increased effectiveness of theory-based interventions should only be used in domains where specific evidence exists to support this cl aim Background : A number of cross‐sectional studies have suggested that higher levels of  sedentary behavior ( SB ) are associated with worse cognitive abilities  in older age . There is a paucity of longitudinal studies investigating this relationship utilizing objective ly assessed SB . This study investigated the relationship between objective ly assessed SB and future cognitive abilities in a cohort of older adults . Methods : A longitudinal study over 22.12 ± 1.46 months including 285 community‐dwelling older adults across 14 regions in Taiwan was undertaken . Cognitive ability was ascertained using a Chinese version of the Ascertain Dementia 8‐item Question naire ( AD8 ) and SB captured by 7 days accelerometer data . Multivariable negative binomial regression models adjusted for confounders were undertaken . Results : 274 community‐dwelling older adults finished the study ( age = 74.6 ± 6.2 , % female = 54.4 % ) . At baseline , 20.1 % ( n = 55 ) , 48.5 % ( n = 133 ) and 31.4 % ( n = 86 ) of the sample engaged in high ( 11 + h ) , medium ( 7–10.99 h ) and low ( < 7 h ) of SB respectively . In the fully adjusted model , higher levels of SB were associated with an increased risk of worse cognitive ability at follow up ( adjusted rate ratio (ARR)1.09 ( 95%CI:1.00–1.19 ) ) , with the strongest relationship evident in those engaging in over 11 h of SB ( ARR 2.27 ( 95%CI:1.24–4.16 ) ) . The relationship remained evident after adjusting for depressive symptoms and physical activity . Conclusion : Our data suggests that objective ly assessed SB , particularly when over 11 h a day , is independently associated with worse cognitive ability over a two year period . Our data adds to the pressing reasons to reduced SB in older age . HighlightsFirst prospect i ve study to investigate objective  ly sedentary behavior ( SB ) and cognition in older adults . Higher levels of objective SB were independently associated with worse cognitive ability over two years . This relationship was most pronounced in older people spending over 11 h a day being sedentary Numerous studies have examined the relationship between physical activity and cognitive function , demonstrating that greater physical activity is associated with lower incidence of cognitive impairment in later life . Due to an increasingly large number of older adults at risk for cognitive impairment , the relationship between physical activity and cognition has garnered increasing public health relevance and multiple r and omized trials have demonstrated that exercise interventions among sedentary adults improve cognitive performance in multiple domains of function . This article will examine the relationship between physical activity and cognitive function by review ing several different areas of literature , including the prevalence of cognitive impairment , assessment methods , observational studies examining physical activity and cognition , and intervention studies . The present review is intended to provide a historical tutorial of existing literature linking  physical activity , exercise , and cognitive function among both healthy and clinical population Background Dementia affects 35 million people worldwide and is currently incurable . Many cases may be preventable because regular participation in physical , mental and social leisure activities during middle age is associated with up to 47 % dementia risk reduction . However , the majority of middle-aged adults are not active enough . MCI is therefore a clear target for activity interventions aim ed at reducing dementia risk . An active lifestyle during middle age reduces dementia risk but it remains to be determined if increased activity reduces dementia risk when MCI is already evident . Before this can be investigated conclusively , complex multimodal activity programmes are required that ( 1 ) combine multiple health promoting activities , ( 2 ) engage people with MCI , and ( 3 ) result in sufficient adherence rates . Methods We design ed the ThinkingFit programme to engage  people with MCI  in a complex intervention comprised of three activity components : physical activity , group-based cognitive stimulation ( GCST ) and individual cognitive stimulation ( ICST ) . Engagement and adherence was promoted by applying specific psychological techniques to enhance behavioural flexibility in an early pre-phase and during the course of the intervention . To pilot the intervention , participants served as their own controls during a 6- to 12-week run-in period , which was followed by 12 weeks of activity intervention . Results Out of 212 MCI patients screened , 163 were eligible , 70 consented and 67 completed the intervention ( mean age 74 years ) .  Activity adherence rates were high : physical activity = 71 % ; GCST = 83 % ; ICST = 67 % . Significant treatment effects ( p < .05 ) were evident on physical health outcomes ( decreased BMI and systolic blood pressure , [ pre/post values of 26.3/25.9 kg/m2 and 145/136 mmHg respectively ] ) , fitness ( decreased resting and recovery heart rate [ 68/65 bpm and 75/69 bpm ] ) , and cognition ( improved working memory [ 5.3/6.3 items ] ) . Conclusions We found satisfactory recruitment , retention and engagement rates , coupled with significant treatment effects in elderly MCI patients . It appears feasible to conduct r and omized controlled trials of the dementia prevention potential of complex multimodal activity programmes like ThinkingFit . Trial registration Clinical Trials.gov registration nr : NCT01603862 ; date : 17/5/2012
Summary Sedentary behaviour is associated with lower cognitive performance , although the attributable risk of sedentary time to all-cause dementia incidence is unclear .
Our systematic review provides evidence that limiting sedentary time and concomitantly engaging in regular moderate-to-vigorous physical activity may best promote healthy cognitive ageing
Aim The increasing rate of all-cause dementia worldwide and the lack of effective pharmaceutical treatments emphasise the value of lifestyle approaches as prevention strategies .
Emerging evidence suggests sedentary behaviour is associated with impaired cognitive function .
A better underst and ing of this association would significantly add to our knowledge of how to best promote healthy cognitive ageing .
Thus , we conducted a systematic review ascertaining the contribution of sedentary behaviour towards associated changes in cognitive function over the adult lifespan .