Combined Dual-Task Gait Training and Aerobic Exercise to Improve Cognition, Mobility, and Vascular Health in Community-Dwelling Older Adults at Risk for Future Cognitive Decline1

Uncorking the limitation-improving dual tasking using transcranial electrical stimulation and task training in the elderly: a systematic review

Introduction

With aging, dual task (DT) ability declines and is more cognitively demanding than single tasks. Rapidly declining DT performance is regarded as a predictor of neurodegenerative disease. Task training and non-invasive transcranial electrical stimulation (tES) are methods applied to optimize the DT ability of the elderly.

Methods

A systematic search was carried out in the PUBMED, TDCS (transcranial direct current stimulation) databases, as well as Web of Science, and a qualitative analysis was conducted in 56 included studies. Aiming to summarize the results of studies that implemented tES, task training, or the combination for improving DT ability and related performance changes in healthy elderly and geriatric patients. For different approaches, the training procedures, parameters, as well as outcomes were discussed.

Results

Task training, particularly cognitive-motor DT training, has more notable effects on improving DT performance in the elderly when compared to the neuromodulation method.

Discussion

Anodal transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex (L-DLPFC), or its combination with task training could be promising tools. However, additional evidence is required from aged healthy people and patients, as well as further exploration of electrode montage.

Aerobic physical exercise versus dual-task cognitive walking in cognitive rehabilitation of people with stroke: a randomized clinical trial

Introduction

Stroke is a neurological deficit caused by an acute focal injury to the central nervous system due to vascular injury that can result in loss of neurological function, lasting brain damage, long-term disability and, in some cases, death. The literature reports that aerobic physical exercise, as well as dual-task cognitive walking, are used for the cognitive recovery of people with stroke. We aimed to assess whether aerobic physical exercise influences post-stroke cognitive recovery, namely performance on selective and sustained attention. We tested the hypothesis that post-stroke aerobic physical exercise leads to more significant gains than post-stroke dual-task cognitive walking.

Methods

We used a Randomized Clinical Trial, single-blind, parallel group, to verify the existence of differences between two groups. A total of 34 patients with subacute to chronic stroke were divided into two groups to train three times a week for 12 weeks: the aerobic physical exercise (PE) group engaged in 20 min on a treadmill, 20 min on a stationary bicycle and 5 min on a desk bike pedal exerciser per session; the dual-task (DT) gait exercise group walked for 45 min while simultaneously performing cognitive tasks per session. All participants were assessed on cognitive functioning with the Mini-Mental State Examination (MMSE) and d2 Test of Attention before acute interventions and post interventions. We have also applied a Visual Analog Scale to monitor the participants' perceived difficulty, pre-, post-acute, and post-chronic interventions. Participants also responded to a Borg Scale of perceived exertion following the acute and the final session of chronic training.

Results

A mixed model ANOVA revealed a significant interaction effect with a large effect size for most of the cognitive variables under study. The variables associated with the d2 Test of Attention showed significant differences between the groups, mainly from T0 to T2. Also for MMSE, an ANOVA revealed a significant interaction effect with significant improvements from T0 to T2. Our results strongly suggest that aerobic physical exercise is more beneficial than dual-task cognitive-gait exercise since in the PE group, cognitive attention scores increase, and cognitive impairment and perception of exertion decrease, compared to the DT group.

Conclusion

These findings support that PE provides more significant benefits for patients post-stroke when compared to DT.

Aerobic exercise and dual-task training combination is the best combination for improving cognitive status, mobility and physical performance in older adults with mild cognitive impairment

AIM

The aim of the present study was to investigate the effects of different exercise combinations on cognitive status, muscle strength of lower extremities, mobility, physical performance, mood and quality of life in older adults with mild cognitive impairment (MCI).

METHODS

A total of 48 older adults with MCI were randomly assigned to four groups: (1) aerobic plus lower extremity strengthening exercises (AG), (2) dual-task training plus lower extremity strengthening exercises (DG), (3) aerobic exercise, dual-task training and lower extremity strengthening exercises (ADG), (4) solely lower extremity strengthening exercises (CG). Patients' cognitive status, lower extremity muscle strength, balance, mobility, activities-specific balance confidence, functional exercise capacity, physical performance, mood and quality of life were evaluated.

RESULTS

In all three intervention groups, there was a significant improvement in cognitive status, balance, mobility, activities-specific balance confidence, physical performance, mood and quality of life (p < 0.05). The most remarkable change was observed in the ADG on cognitive status, mobility and physical performance parameters (p < 0.05). In addition, the most significant improvement in balance parameters was recorded both in the DG and ADG (p < 0.05). Besides, the highest increase in functional exercise capacity was detected both in the AG and ADG (p < 0.05). On the other hand, both exercise combinations were superior to the control group in terms of improving mood and quality of life (p < 0.05).

CONCLUSION

The trial results proved that aerobic exercise and dual-task training is the best combination for improving cognitive status, mobility and physical performance in older adults with MCI.

Multicomponent exercise program effects on fitness and cognitive function of elderlies with mild cognitive impairment: Involvement of oxidative stress and BDNF

Regular exercise has been shown to be one of the most important lifestyle influences on improving functional performance, and decreasing morbidity and all-cause mortality among older people. However, although there is some evidence on the effects of aerobic training on oxidative stress, there is little information regarding the effects of multicomponent exercise (dual-task training) and combination of exercise with cognitive stimulation on oxidative stress. In this context, the aim of this study was to verify the effects of a multicomponent exercise program on physical fitness and cognitive function in the elderly with mild cognitive impairment and determine the role of oxidative stress and brain-derived neurotrophic factor (BDNF). At baseline, 37 elderly nursing home residents with mild cognitive impairment were divided into two groups: the control group (CG, n = 12, 81.8 years) and the experimental group (EG, n = 25, 83.2 years). These elderlies followed multicomponent exercise training for 24 weeks, with two sessions per week and 45–50 min per session. The exercises included both aerobic and strength exercises, considering functional movements and light to moderate intensity. Cognitive stimulation comprehended exercises based on word games, puzzles, mathematical calculations, forward and backward counting, computer exercises, exergames, and games on a balanced platform. Physical assessments (weight, height, and body mass index), health and functional parameters (fitness tests: chair stand, arm curls, chair sit-and-reach, eight feet up-and-go, back scratch, 6-min walking, feet together, semi-tandem, and full tandem), lipid profile (total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides), measures of lipid peroxidation damage, thiobarbituric acid reactive substances (TBARS), total antioxidant capacity (TAC), and BDNF were measured in plasma, based on which analyses were performed before and after the 24 weeks of the multicomponent exercise intervention. The results showed an overall improvement in physical and functional performance. Regarding biochemical measures, multicomponent exercises lead to a significant decrease in oxidative damage. The results indicate that multicomponent exercise training induces benefits in functional capacity and reduces damage due to oxidative stress.

Development of a Combined Exercise and Cognitive Stimulation Intervention for People with Mild Cognitive Impairment-Designing the MEMO_MOVE PROGRAM

Dementia patients are at high risk for the decline of both physical and cognitive capacities, resulting in an increased risk of the loss of autonomy. Exercise is regarded as a non-pharmacological therapy for dementia, considering the potential benefits of preventing cognitive decline and improving physical fitness. In this paper, we aim to describe the different design stages for an exercise program combined with cognitive stimulation for a population with mild cognitive impairment, i.e., the MEMO_MOVE program.

METHODS

The intervention design followed the Medical Research Council's guidelines for complex interventions and was structured according to the six steps in quality intervention development (6SQuID). The intervention was described considering the Template for Intervention Description and Replication (TIDieR). In order to establish the intervention characteristics, a literature review was conducted to collate and analyze previous work, which provided a summary the type of exercise that should be implemented among this population.

RESULTS

The MEMO_MOVE program was structured and described, regarding (i) inclusion of a cognitive stimulation component; (ii) the kind of cognitive stimulation; and (iii) the type of exercise, duration, frequency, intensity, and program length.

CONCLUSIONS

A systematic step-by-step process design was followed to create a specific intervention to promote physical fitness and cognitive stimulation in individuals with mild dementia.

Influence of Aerobic Exercise Load Intensity on Children's Mental Health

As people have become more aware in recent years, aerobic physical exercise plays an important role in alleviating people's mental health problems. However, traditionally, it is believed that young children do not have mental health problems. To help people change this fixed idea, and to study how to correctly adjust the load intensity of aerobic physical exercise under the condition of limited physical fitness of young children, and accurately help children's mental health development, this paper studies the influence of aerobic physical exercise load intensity on children's mental health. In this paper, the detection and tracking technology of video moving objects is used to analyze the data of the research object. This technique includes several commonly used and improved video analysis algorithms. The use of moving target and tracking technology and algorithms can completely extract moving targets, eliminate the phenomenon of void and nothingness, and improve data acquisition and analysis capabilities. The results show that taking part in aerobic exercise with appropriate intensity is beneficial to regulating children's emotional state, reducing their psychological burden, enhancing their negative energy resistance, and arousing their positive participation. Compared with before aerobic exercise, the learning efficiency was improved by 6.36%.

Mix-and-Match or Mismatch? Exploring the Perspectives of Older Adults About Zumba Dance and Its Potential Utilization for Dual-Task Training

Despite the popularity of Zumba dancing, research is scarce about its impact on older adults. Meanwhile, the integration of cognitive tasks with physical exercises, also known as dual tasking, is an evolving strategy to facilitate activities for older adults. This study investigated the perceptions of persons aged ≥55 years on Zumba and its potential to be incorporated into a dual-task program. We conducted a descriptive-qualitative study involving 44 Filipino older adults. Using content analysis, four themes were identified: moving toward match or mismatch, balancing benefits with burdens, dual tasking as innovative yet potentially challenging, and overcoming barriers with enablers. Although Zumba was perceived as an inclusive and beneficial activity, individual and contextual limitations could hinder its suitability. Moreover, dual tasking in Zumba was considered an innovative approach, although challenges should be addressed to promote its feasibility. Several strategies could enable the design and implementation of age-appropriate Zumba and dual-tasking programs for older adults.

Effects of Exergame-Based Dual-Task Training on Executive Function and Dual-Task Performance in Community-Dwelling Older People: A Randomized-Controlled Trial

Objective: Aging is associated with decline in executive function that may lead to reduced dual-task performance. Regular exercise has been recommended for promoting or maintaining mental and physical health in older adults, yet only a fraction of older adults exercise regularly. Exergame training may have the potential to enhance exercise adherence. Therefore, the aim of this study was to examine the effects of exergame-based dual-task training on executive function and dual-task performance in community-dwelling older adults. Materials and Methods: This was a single-blinded, randomized-controlled trial. Twenty community-dwelling older adults were recruited and randomly assigned to one of two groups. All participants completed 36 trainings, including three 60-minute sessions/week over 12 weeks. Participants in the experimental group received exergame-based dual-task training, while those in the control group received home-based multicomponent exercise training. Measures of executive function, dual-task performance, and community walking ability were assessed before and after the intervention. Results: Significant group × time interactions (P = 0.000-0.027) with large effects were found in all selected outcome measures. Compared with the control group, the experimental group improved significantly in measures of general executive function (P = 0.014), inhibitory control (P = 0.037), cognitive dual-task performance (P < 0.001), and community walking ability (P = 0.002). Enhanced general executive function was highly correlated with either improved motor dual-task performance (r = 0.674) or improved cognitive dual-task performance (r = -0.701). Conclusion: These results suggested that exergame-based dual-task training improved both executive function and dual-task performance in older people. These positive effects could be transferred to enhance community walking ability. Clinical Trial Registration number: ACTRN 12617000095369.

Changes in Metabolic Activity and Gait Function by Dual-Task Cognitive Game-Based Treadmill System in Parkinson's Disease: Protocol of a Randomized Controlled Trial

Balance and gait impairments, and consequently, mobility restrictions and falls are common in Parkinson’s disease (PD). Various cognitive deficits are also common in PD and are associated with increased fall risk. These mobility and cognitive deficits are limiting factors in a person’s health, ability to perform activities of daily living, and overall quality of life. Community ambulation involves many dual-task (DT) conditions that require processing of several cognitive tasks while managing or reacting to sudden or unexpected balance challenges. DT training programs that can simultaneously target balance, gait, visuomotor, and cognitive functions are important to consider in rehabilitation and promotion of healthy active lives. In the proposed multi-center, randomized controlled trial (RCT), novel behavioral positron emission tomography (PET) brain imaging methods are used to evaluate the molecular basis and neural underpinnings of: (a) the decline of mobility function in PD, specifically, balance, gait, visuomotor, and cognitive function, and (b) the effects of an engaging, game-based DT treadmill walking program on mobility and cognitive functions. Both the interactive cognitive game tasks and treadmill walking require continuous visual attention, and share spatial processing functions, notably to minimize any balance disturbance or gait deviation/stumble. The ability to “walk and talk” normally includes activation of specific regions of the prefrontal cortex (PFC) and the basal ganglia (site of degeneration in PD). The PET imaging analysis and comparison with healthy age-matched controls will allow us to identify areas of abnormal, reduced activity levels, as well as areas of excessive activity (increased attentional resources) during DT-walking. We will then be able to identify areas of brain plasticity associated with improvements in mobility functions (balance, gait, and cognition) after intervention. We expect the gait-cognitive training effect to involve re-organization of PFC activity among other, yet to be identified brain regions. The DT mobility-training platform and behavioral PET brain imaging methods are directly applicable to other diseases that affect gait and cognition, e.g., cognitive vascular impairment, Alzheimer’s disease, as well as in aging.

Effects of Combined Physical Activity and Cognitive Training on Cognitive Function in Older Adults with Subjective Cognitive Decline: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background. Subjective cognitive decline (SCD) is recognized as the earliest prodromal stage of Alzheimer’s disease (AD). Emerging studies explored the effects of combined physical activity and cognitive training interventions on cognitive ability, psychological well-being, and emotion of older adults with SCD, but the results are now still controversial. Objective. This study systematically evaluated the enhancement effects of the combined physical-cognitive interventions on memory self-efficacy, objective cognitive function, psychological well-being, and emotion of older adults with SCD. Methods. Data sources PubMed, EMBASE, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang degree and conference papers database, Chinese Science and Technology Periodical (VIP) databases from their inception to 28 February 2020, the Cochrane Central Register of Controlled Trials (Cochrane Library, 2020, Issue 3), and the reference lists of all retrieved articles were searched. Data analysis and bias risk evaluation were conducted in 2020. Two reviewers (SG and YY) independently evaluated the risk of bias of the included studies using the RoB 2 tool. Results. Eleven RCTs involving 1713 participants with SCD (age 68.0 ± 6.1) were included for review and meta-analysis. The interventions in the included studies were physical activity combined with cognitive training. Multiple-modality exercise with mind-motor training, supervised strategy-based memory training sequentially after stationary cycling, Dejian Mind-Body intervention, and physical activity and cognitive stimulation were also practiced. Conclusions. Compared to the active or nonactive control groups, the combined interventions are effective in improving objective cognitive function in SCD which may show the potential value of combined physical-cognitive interventions in improving objective cognitive ability and preventing the conversion of SCD to MCI or AD and no adverse effects. However, owing to the limitations of the included studies, these findings should be interpreted cautiously.

The Benefits of High-Intensity Interval Training on Cognition and Blood Pressure in Older Adults With Hypertension and Subjective Cognitive Decline: Results From the Heart & Mind Study

Background: The impact of exercise on cognition in older adults with hypertension and subjective cognitive decline (SCD) is unclear.

Objectives: We determined the influence of high-intensity interval training (HIIT) combined with mind-motor training on cognition and systolic blood pressure (BP) in older adults with hypertension and SCD.

Methods: We randomized 128 community-dwelling older adults [age mean (SD): 71.1 (6.7), 47.7% females] with history of hypertension and SCD to either HIIT or a moderate-intensity continuous training (MCT) group. Both groups received 15 min of mind-motor training followed by 45 min of either HIIT or MCT. Participants exercised in total 60 min/day, 3 days/week for 6 months. We assessed changes in global cognitive functioning (GCF), Trail-Making Test (TMT), systolic and diastolic BP, and cardiorespiratory fitness.

Results: Participants in both groups improved diastolic BP [F_{(1, 87.32)} = 4.392, p = 0.039], with greatest effect within the HIIT group [estimated mean change (95% CI): −2.64 mmHg, (−4.79 to −0.48), p = 0.017], but no between-group differences were noted (p = 0.17). Both groups also improved cardiorespiratory fitness [F_{(1, 69)} = 34.795, p < 0.001], and TMT A [F_{(1, 81.51)} = 26.871, p < 0.001] and B [F_{(1, 79.49)} = 23.107, p < 0.001]. There were, however, no within- or between-group differences in GCF and systolic BP at follow-up.

Conclusion: Despite improvements in cardiorespiratory fitness, exercise of high- or moderate-intensity, combined with mind-motor training, did not improve GCF or systolic BP in individuals with hypertension and SCD.

Clinical Trial Registration:ClinicalTrials.gov (NCT03545958).

Evaluating the Feasibility and Effects of a Short-Term Task Specific Power Training With and Without Cognitive Training Among Older Adults With Slow Gait Speed: A Pilot Study

Objective:

To investigate the feasibility and efficacy of short-term functional power training and further examine whether the addition of cognitive training targeting sustained attention and inhibitory control would augment the effect on the outcomes.

Design:

Randomized pilot study.

Setting:

Clinical research facility.

Participants:

Community-dwelling primary care patients (N=25) aged >65 years with mobility limitation within the VA Boston Healthcare System.

Interventions:

Participants were randomly assigned to either functional power training (n=14) or functional power+cognitive training (n=11), offered 3 times a week for 6 weeks. Session durations were either 70 minutes (functional power+cognitive training) or 40 minutes (functional power training).

Main Outcome Measures:

We evaluated feasibility (dropouts, attendance), mobility performance (Short Physical Performance Battery [SPPB]), leg power [stair climb test]), dynamic balance [figure-of-8], and gait characteristics [gait speed, stance time, step width, swing time, step length, variabilities under single-task and dual-task conditions]). Nonparametric analyses were used to compare overall pre-post changes and between-group differences.

Results:

Of the 39 veterans screened, 25 were randomized and enrolled. Twenty-one men with a mean age 76±7 years completed the study; 86% were white. Participants had a mean SPPB score of 8.3±1.6 out of 12. For those completing the study, overall attendance was 79%. Among all participants, clinically relevant and/or statistically significant median change in mobility performance (∆1 point), leg power (∆25.0W), dynamic balance (∆-1.1s), and gait characteristics (gait speed [∆0.08s, ∆0.09s], step length [∆1.9cm, ∆3.8cm], and stance time [∆-0.02s, ∆-0.05s] under single- and dual-task, respectively) were observed after 6 weeks of training. There were no statistically significant group differences in dropouts, attendance rate, or any of the outcomes based on cognitive training status.

Conclusions:

Short-term functional power training with or without a cognitive training led to clinically meaningful improvements in mobility performance, leg power, dynamic balance, and gait characteristics. These findings add to the body of evidence supporting the benefits of functional power training on clinically relevant outcomes. Additional cognitive training did not have an added effect on the study outcomes from our study. Further research is needed.

Dual-Task Exercise to Improve Cognition and Functional Capacity of Healthy Older Adults

Background

It has been suggested that physical inactivity and lack of stimulating cognitive activity are the two most significant modifiable risk factors to impair cognitive function. Although many studies that investigated the cognitive effects of physical exercise and cognitive stimuli in dual-task conditions showed improved cognitive performance, others have not confirmed these findings. The main aim of the present work is to analyze the effects of a dual-task multimodal physical exercise training, at moderate intensity, and cognitive stimulation on cognitive and physical function in healthy older adults.

Methods

This clinical trial was registered on the Brazilian Registry of Clinical Trials (RBR-9zrx3d). Here we tested the effects of a dual-task multimodal physical exercise training, at moderate intensity, on cognitive and physical function and quality of life in community dwelling older adults. The training protocol included 24 group sessions, 2/week, per 75 min. Cognition was assessed using CANTAB automated neuropsychological tests and Functional Capacity to Exercise tests. Performance was compared from baseline to post intervention and to a non-exercise control group using Mixed Linear Model for repeated measures.

Results

Control (CG) and dual-task (DTEx) groups progressed differentially over time on performance of episodic memory, sustained visual attention, functional mobility, cardiorespiratory fitness, lower limbs strength resistance, agility, quality of life and dual-task performance with significant improved DTEx performance. Control group did not show any significant changes on these tests except for showing a reduction in dual-task performance.

Conclusion

We suggest that the dual-task combination of multisensory cognitive stimulation and multimodal moderate physical exercise training, twice a week, may be adopted as an effective program to reduce progression of age-related cognitive decline and improve physical fitness and quality of life on healthy older adults.

Clinical Trial Registration

Brazilian Registry of Clinical Trials: https://ensaiosclinicos.gov.br/rg/RBR-9zrx3d -UTN code: U1111-1233-6349.

Dual-Task Training Program for Older Adults: Blending Gait, Visuomotor and Cognitive Training

Objective: Physical and cognitive impairments are common with aging and often coexist. Changes in the level of physical and mental activity are prognostic for adverse health events and falls. Dual-task (DT) training programs that can improve mobility and cognition simultaneously can bring significant improvements in rehabilitation. The objective of this mixed methods exploratory RCT was to provide evidence for the feasibility and therapeutic value of a novel game-assisted DT exercise program in older adults. Methods: Twenty-two community dwelling participants, between the ages of 70-85 were randomized to either dual-task treadmill walking (DT-TR) or dual-task recumbent bicycle (DT-RC). Both groups viewed a standard LED computer monitor and performed a range of cognitive game tasks while walking or cycling; made possible with the use of a "hands-free", miniature, inertial-based computer mouse. Participants performed their respective 1-h DT exercise program twice a week, for 12 weeks at a community fitness centre. Semi-structured interviews and qualitative analysis was conducted to evaluate the participant's experiences with the exercise program. Quantitative analysis included measures of standing balance, gait function (spatiotemporal gait variable), visuomotor and executive cognitive function, tested under single and DT walking conditions. Results: Compliance was 100% for all 22 participants. Four themes captured the range of participant's experiences and opinions: 1) reasons for participation, 2) difficulties with using the technologies, 3) engagement with the computer games, and 4) positive effects of the program. Both groups showed significant improvements in standing balance performance, visuomotor and visuospatial executive function. However, significant improvement in dual task gait function was observed only in the DT-TR group. Medium to large effect sizes were observed for most balance, spatiotemporal gait variables, and cognitive performance measure. Conclusion: With only minor difficulties with the technology being reported, the findings demonstrate feasible trial procedures and acceptable DT oriented training with a high compliance rate and positive outcomes. These findings support further research and development, and will direct the next phase of a full-scale RCT.

The Interaction between Mobility Status and Exercise Specificity in Older Adults

Many adults older than 60 yr experience mobility limitations. Although physical exercise improves older adults' mobility, differences in baseline mobility produce large variations in individual responses to interventions, and these responses could further vary by the type and dose of exercise. Here, we propose an exercise prescription model for older adults based on their current mobility status.

Double-task exercise programmes to strengthen cognitive and vascular health in older adults at risk of cognitive decline: protocol for a randomised clinical trial

INTRODUCTION

Cognitive and physical declines are frequent causes of disability among older adults (OAs) in Mexico that imposes significant burden on the health system and OAs' families. Programmes to prevent or delay OAs' cognitive and physical decline are scarce.

METHODS AND ANALYSIS

A double-blind randomised clinical trial will be conducted. The study will aim to evaluate two 24-week double-task (aerobic and cognitive) square-stepping exercise programmes for OAs at risk of cognitive decline-one programme with and another without caregiver participation-and to compare these with an aerobic-balance-stretching exercise programme (control group). 300 OAs (100 per group) affiliated with the Mexican Institute of Social Security (IMSS) between 60 and 65 years of age with self-reported cognitive concerns will participate. They will be stratified by education level and randomly allocated to the groups. The intervention will last 24 weeks, and the effect of each programme will be evaluated 12, 24 and 52 weeks after the intervention. Participants' demographic and clinical characteristics will be collected at baseline. The outcomes will include: (1) general cognitive function; (2) specific cognitive functions; (3) dual-task gait; (4) blood pressure; (5) carotid intima-media thickness; (6) OAs' health-related quality of life; and (7) caregiver burden. The effects of the interventions on each outcome variable will be examined using a repeated-measures analysis of variance (ANOVA), with study groups as the between-subjects variable and time as the within-subject variable.

ETHICS AND DISSEMINATION

The study was approved by the IMSS Ethics and Research Committees (registration number: 2018-785-095). All participants will sign a consent form prior to their participation. The study results will be disseminated to the IMSS authorities, healthcare providers and the research community.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT04068376).

Imaging Cerebral Glucose Metabolism during Dual-Task Walking in Patients with Parkinson's disease

BACKGROUND AND PURPOSE

Gait impairment is a hallmark of Parkinson's disease (PD). Natural walking involves more cognitive demand than treadmill walking or in-laboratory walking tests because patients have to actively work on navigation and top-down cognitive control which taxes cognitive reserve in the prefrontal cortex. To mimic the prefrontal engagement occurring with natural walking in a controlled and safe environment, dual-task (DT) treadmill walking has been developed. In this study, we tested the feasibility of imaging DT walking-related changes in brain glucose metabolism in patients with PD.

METHODS

Fifteen patients with PD were scanned with fluorodeoxyglucose (FDG) positron emission tomography. Five patients performed DT walking, and 10 patients were rested during the FDG uptake period. First, the images were contrasted between the groups. Second, the walking-related brain glucose metabolism was inspected at the individual level.

RESULTS

Consistently increased glucose metabolism was identified in DT walking versus rest in the primary visual/sensorimotor areas, thalamus, superior colliculus, and cerebellum. In individual level analysis, patients with less progressed disease (n = 3) showed prefrontal activity during DT walking while patients with more progressed disease (n = 2) did not.

CONCLUSION

This study confirms the feasibility of imaging glucose metabolism during DT walking in patients with PD. We also report that during DT walking, there is a lesser degree of prefrontal engagement in the patients with more progressed disease compared to those with less progressed disease, implying increased degrees of frontal dysfunction with PD progression.

The effect of dual-task training on cognition of people with different clinical conditions: An overview of systematic reviews

BACKGROUND

The number of patients with cognitive impairment increases as the population becomes older. This perspective may persist a burden on health care systems unless considered new options of prevention and treatment. The aim of this meta-synthesis is to analyze different systematic reviews on the effectiveness of dual-task training (DTT) on cognition and motor function of different people.

METHODS

A systematic search of systematic reviews published until October 2019 was conducted in PubMed/Medline, Scopus and Cochrane databases addressing studies which investigated the effect of DTT compared to control or other intervention on cognitive functions of healthy or unhealthy individuals. Three steps were followed to retrieve studies: reading title, abstract and full text. Checklist Assessing the Methodological Quality of Systematic Reviews (AMSTAR) was used to assess the quality of selected articles.

RESULTS

In terms of quality of evidence, according to AMSTAR, 62.5 % of the reviews were rated as being "low" and 37.5 % were graded as "moderate" quality. Two main themes were identified among the studies' outcomes: Improvement on mobility performance or postural stability; and beneficial effect on cognitive function. In terms of effect size, there were reported an important variation, having more significant results for findings involving mobility and modest effect for findings regarding cognitive function.

CONCLUSION

People with different clinical conditions could benefit from dual-task training. The benefits may encompass general cognitive functions, memory, physical performance, gait and balance, to name a few aspects.

The Potential Mediation of the Effects of Physical Activity on Cognitive Function by the Gut Microbiome

The population of older adults is growing dramatically worldwide. As older adults are at greater risk of developing disorders associated with cognitive dysfunction (i.e., dementia), healthcare costs are expected to double by 2040. Evidence suggests dementia may be slowed or prevented by lifestyle interventions, including physical activity (PA). PA is associated with improved cognitive function and may reduce risk for dementia by mitigating known risk factors (i.e., cardiovascular diseases) and/or by enhancing neurochemical processes. An emerging area of research suggests the gut microbiome may have similar neuroprotective effects. Altering the gut microbiome has been found to target physiological processes associated with dementia risk, and it influences gut-brain-microbiome axis signaling, impacting cognitive functioning. The gut microbiome can be altered by several means (i.e., disease, diet, prebiotics, probiotics), including PA. As PA and the gut microbiome independently influence cognitive function and PA changes the composition of the gut microbiome, cognitive improvement due to PA may be partially mediated by the gut microbiome. The present article provides an overview of the literature regarding the complex associations among PA, cognitive function, and the gut microbiome, as well as their underlying biological mechanisms. A comprehensive, theoretical model integrating evidence for the potential mediation is proposed.

Rationale and protocol of the StayFitLonger study: a multicentre trial to measure efficacy and adherence of a home-based computerised multidomain intervention in healthy older adults

Background

In older adults, multidomain training that includes physical and cognitive activities has been associated with improvement of physical and cognitive health. The goal of the multisite StayFitLonger study is to assess a home-based computerised training programme, which combines physical exercises, stimulating cognitive activities and virtual coaching.

Methods

One hundred twenty-eight cognitively healthy older adults will be recruited from the community in Switzerland, Canada and Belgium. The study will comprise (1) a 26-week double-blind randomized controlled efficacy trial and (2) a 22-week pragmatic adherence sub-study. In the efficacy trial, participants will be randomly assigned to an experimental or an active control intervention. In the experimental intervention, participants will use the StayFitLonger programme, which is computerised on a tablet and provides content that combines physical activities with a focus on strength and balance, as well as divided attention, problem solving and memory training. Outcomes will be measured before and after 26 weeks of training. The primary efficacy outcome will be performance on the “Timed-Up & Go” test. Secondary outcomes will include measures of frailty, cognition, mood, fear of falling, quality of life, and activities of daily living. Age, sex, education, baseline cognition, expectation, and adherence will be used as moderators of efficacy. Following the 26-week efficacy trial, all participants will use the experimental programme meaning that participants in the control group will ‘cross over’ to receive the StayFitLonger programme for 22 weeks. Adherence will be measured in both groups based on dose, volume and frequency of use. In addition, participants’ perception of the programme and its functionalities will be characterised through usability, acceptability and user experience.

Discussion

This study will determine the efficacy, adherence and participants’ perception of a home-based multidomain intervention programme and its functionalities. This will allow for further development and possible commercialization of a scientifically validated training programme.

Trial registration

ClinicalTrials.gov, NCT04237519 Registered on January 22, 2020 - Retrospectively registered.

Effects of Transcranial Direct Current Stimulation Over the Dorsolateral Prefrontal Cortex (PFC) on Cognitive-Motor Dual Control Skills

This randomized crossover study investigated whether anodal transcranial direct current stimulation (tDCS) over the dorsolateral prefontal cortex (dlPFC) modulates memory-guided finger isometric maintenance during single motor and dual cognitive-motor tasks, based on electroencephalogram (EEG) signals. Twenty-three healthy participants (14 female; M age = 29.130 years, SD = 10.918) underwent both sham and 2-mA stimulation sessions over the dlPFC for 20 minutes, with a minimum washout period of seven days. We analyzed finger-force isometric maintenance and event-related spectral perturbation (ERSP) of the EEG during early and later phases of both tasks. We observed a significant motor accuracy improvement (p = .014) and significant variation of force output (p = .027) with significant decrease in ERSP on the dorsomedial prefrontal cortex (dmPFC) (early phase, p = .027; later phase, p = .023) only after 2 mA stimulation. Thus, anodal tDCS over the dlPFC may improve memory-guided force control during cognitive-motor dual tasks.

The effects of cognitive-motor training interventions on executive functions in older people: a systematic review and meta-analysis

Background

Ageing is associated with physical and cognitive decline, affecting independence and quality of life in older people. Recent studies show that in particular executive functions are important for daily-life function and mobility. This systematic review investigated the effectiveness of cognitive-motor training including exergaming on executive function (EF, set-shifting, working memory, inhibitory control) in healthy older people.

Methods

An electronic database search for randomised controlled trials (RCT), controlled clinical trials (CCT) and parallel group trials was performed using MEDLINE, EMBASE, and PsychINFO following PRISMA guidelines. Inclusion criteria were: (1) community-dwelling participants > 60 years without a medical condition or medical treatment, (2) reporting at least one cognitive-motor intervention while standing or walking, (3) use of dual-task interventions using traditional methods or modern technology to deliver a cognitive-motor task, (4) inclusion of at least one cognitive outcome. The PEDro scale was used for quality assessment.

Results

A total of 1557 studies were retrieved, of which 25 studies were included in this review. Eleven studies used a technology-based dual-task intervention, while 14 trials conducted a general cognitive-motor training. The age range of the cohort was 69 to 87 years. The interventions demonstrated positive effects on global cognitive function [mean difference 0.6, 95% CI 0.29–0.90] and inhibitory control [mean difference 0.61, 95% CI 0.28–0.94]. Effects were heterogeneous (I² range: 60–95) and did not remain after a sensitivity analysis. Processing speed and dual-task costs also improved, but meta-analysis was not possible.

Conclusion

Cognitive-motor and technology-based interventions had a positive impact on some cognitive functions. Dual-task interventions led to improvements of domains related global cognitive functions and inhibitory control. Likewise, technology-based exergame interventions improved functions related to processing speed, attentional and inhibitory control. Training interventions with a certain level of exercise load such as progression in difficulty and task specificity were more effective to gain task-related adaptations on cognitive functions.

InVestiGation of the Association of Physical Activity and Sedentary Behavior with tHe Occurrence of Future Cardiovascular Disease and Long Term Outcome in General Population Using the HEALTHCARE Database (VGH-HEALTHCARE)

BACKGROUND

Current evidence supports the beneficial effect of physical activity in reducing adverse events, however studies on Asian populations are limited and have reported inconsistent findings. The aim of this study was to investigate the association between physical activity and the development of cardiovascular disease, diabetes, hypertension and malignancy in a large Asian cohort. We also investigated interactions between the intensity of physical activity, environmental exposure and biochemical markers.

METHODS

Subjects who received annual checkups at Taipei Veterans General Hospital were invited to join this study. Information on physical activity was evaluated using the International Physical Activity Questionnaire Short Form (IPAQ-SF). Associations between the occurrence of clinical events including cardiovascular events, diabetes and malignancies and the intensity of physical activity, biochemical markers, imaging findings, personality trait evaluations and nutrition were evaluated.

RESULTS

In the initial stage of this study, a total of 1010 patients enrolled, 626 (62%) were male, 74 (7.4%) had diabetes, 183 (18.3%) had hypertension, and 220 (21.8%) were smokers. The total cholesterol was 202.1 ± 36.2 mg/dL and low-density lipoprotein-cholesterol was 125.7 ± 32.9 mg/dL, including 49.3 ± 13.1 mg/dL for serum high-density lipoprotein-cholesterol and 120.7 ± 70.7 mg/dL for triglycerides. The fasting glucose level was 93.8 ± 21.9 mg/dL, and HbA1c was 5.7 ± 0.7%. All information collected will be incorporated with future events to analyze the relationship between biochemical parameters, physical activity and future adverse events.

CONCLUSIONS

These findings will contribute to the understanding of the value of physical activity in determining future cardiovascular and non-cardiovascular events in Asian populations.

Environmental Enrichment and Successful Aging

The human brain sustains a slow but progressive decline in function as it ages and these changes are particularly profound in cognitive processing. A potential contributor to this deterioration is the gradual decline in the functioning of multiple sensory systems and the effects they have on areas of the brain that mediate cognitive function. In older adults, diminished capacity is typically observed in the visual, auditory, masticatory, olfactory, and motor systems, and these age-related declines are associated with both a decline in cognitive proficiency, and a loss of neurons in regions of the brain. We will review how the loss of hearing, vision, mastication skills, olfactory impairment, and motoric decline accompany cognitive loss, and how improved functioning of these systems may aid in the restoration of the cognitive abilities in older adults. The human brain appears to require a great deal of stimulation to maintain its cognitive efficacy as people age and environmental enrichment may aid in its maintenance and recovery.

The Impact of Blood Pressure Dipping Status on Cognition, Mobility, and Cardiovascular Health in Older Adults Following an Exercise Program

Objectives: To determine whether a dual-task gait and aerobic exercise intervention differentially impacted older adults with normal blood pressure (BP) dipping status (dippers) compared to those with nondipping status (nondippers). Methods: This study was a secondary analysis involving participants (mean age = 70.3 years, 61% women) who attended a laboratory-based exercise intervention over a 6-month period (40 min/day and 3 days/week). Participants were assessed in measures of cognition, mobility, and cardiovascular health at baseline, 3, 6, and 12 months (after a 6-month no-contact follow-up). Results: We observed improvements in cognition in both groups at 6 and 12 months, although no between-group differences were seen. Nondippers demonstrated superior improvements in usual gait velocity and step length after the exercise intervention compared to dippers. Dippers reduced daytime systolic BP at 6 and 12 months to a greater extent than nondippers. Discussion: BP dipping status at baseline did not influence exercise benefits to cognition but did mediate changes in mobility and cardiovascular health.

Effect of interactive cognitive motor training on gait and balance among older adults: A randomized controlled trial

BACKGROUND

Aging is a normal degenerative process that results in a decline in the gait and balance performance of older adults. Interactive cognitive motor training is an intervention that integrates cognitive and motor tasks to promote individuals' physical and cognitive fall risk factors. However, the additive effects of the interactive cognitive motor training on objective quantitative data and comprehensive descriptions of gait and balance warrants further investigation.

OBJECTIVES

To investigate the effect of interactive cognitive motor training on older adults' gait and balance from immediate to long-term time points.

DESIGN

A double-blind randomized control trial.

SETTINGS

Four senior service centers and community service centers in Taiwan.

PARTICIPANTS

62 older adults who met the inclusion criteria.

METHODS

The study participants were older adults without cognitive impairment, and they were randomly allocated to the experimental group or active control group. In both groups, older adults participated in three sessions of 30-min training per week for a total of 8 weeks, with the total number of training sessions being 24. The primary outcome was gait performance, which was measured using objective and subjective indicators. iWALK was used as an objective indicator to measure pace and dynamic stability; the Functional Gait Assessment was employed as a subjective indicator. The secondary outcome was balance performance, which was measured using iSWAY. A generalized estimating equation was used to identify whether the results of the two groups differ after receiving different intervention measures; the results were obtained from immediate to long-term posttests.

RESULTS

Stride length in the pace category of the experimental group improved significantly in immediate posttest (p = 0.01), 3-month follow-up (p = 0.01), and 6-month follow-up (p = 0.04). The range of motion of the leg exhibited significant improvement in immediate posttest (p = 0.04) and 3-month follow-up (p = 0.04). The Functional Gait Assessment result indicated that statistically significant improvement was observed in immediate posttest (p = 0.02) and 12-month follow-up (p = 0.01). The results of balance performance showed that the experimental group attained statistically significant improvement in centroid frequency in the immediate posttest (p = 0.02).

CONCLUSIONS

The research results validated that the 24 sessions of the interactive cognitive motor training intervention significantly improved gait and balance performance. Future studies should extend the sample to communities to promote the gait and balance performance of community-dwelling older adults without cognitive impairment and reduce their risk of falling and developing gait-related diseases.

Association of adiponectin with cognitive function precedes overt diabetes in the Brazilian Longitudinal Study of Adult Health: ELSA

BACKGROUND

Adiponectin is an insulin-sensitizer adipocytokine endowed with neuroprotective actions. Whether adiponectin regulates neuronal functioning toward delaying cognitive decline independently of the glucose metabolism disturbance has been poorly explored. This study evaluated if the performance in cognitive tests was associated with adiponectin levels prior the development of type 2 diabetes in middle-aged individuals.

METHODS

A sample of 938 non-diabetic participants of ELSA had their cognitive function assessed by the CERAD delayed word recall test, the verbal fluency test and the trail making test. Stepwise multiple linear regression using forward selection had the response to cognitive tests as the dependent variable and adiponectin as the independent variable of main interest, adjusted for glucose tolerance status and confounders.

RESULTS

Mean age was 45.7 ± 4.9 years, 54.5% were women, 43.0% had high education level, 59.3% weight excess and 70.0% prediabetes. In crude model, only the delayed recall memory was associated with adiponectin levels. In an initial regression model, delayed recall memory remained independently associated with adiponectin levels and prediabetes. After complete adjustments, adiponectin but not prediabetes maintained independently associated with delayed recall memory (β 0.067; 95% CI 0.006-0.234; p = 0.040). On the other hand, learning memory showed to be associated with prediabetes (β 0.71 95% CI 0.17; 1.24; p = 0.009) but not with adiponectin.

CONCLUSIONS

The association of memory with adiponectin in middle-aged individuals, prior overt diabetes, suggests that this adipocytokine could anticipate cognitive impairmentρ detection, when preventive strategies could be more effectively implemented. The usefulness of adiponectin to identify increased risk for cognitive dysfunction before advanced age needs to be prospectively investigated in ELSA cohort.

Multiple-modality exercise and mind-motor training to improve mobility in older adults: A randomized controlled trial

OBJECTIVE

To investigate the effects of multiple-modality exercise with or without additional mind-motor training on mobility outcomes in older adults with subjective cognitive complaints.

METHODS

This was a 24-week randomized controlled trial with a 28-week no-contact follow-up. Community-dwelling older adults underwent a thrice -weekly, Multiple-Modality exercise and Mind-Motor (M4) training or Multiple-Modality (M2) exercise with an active control intervention (balance, range of motion and breathing exercises). Study outcomes included differences between groups at 24weeks and after the no-contact follow-up (i.e., 52weeks) in usual and dual-task (DT, i.e., serial sevens [S7] and phonemic verbal fluency [VF] tasks) gait velocity, step length and cycle time variability, as well as DT cognitive accuracy.

RESULTS

127 participants (mean age 67.5 [7.3] years, 71% women) were randomized to either M2 (n=64) or M4 (n=63) groups. Participants were assessed at baseline, intervention endpoint (24weeks), and study endpoint (52weeks). At 24weeks, the M2 group demonstrated greater improvements in usual gait velocity, usual step length, and DT gait velocity (VF) compared to the M4 group, and no between- or within-group changes in DT accuracy were observed. At 52weeks, the M2 group retained the gains in gait velocity and step length, whereas the M4 group demonstrated trends for improvement (p=0.052) in DT cognitive accuracy (VF).

CONCLUSIONS

Our results suggest that additional mind-motor training was not effective to improve mobility outcomes. In fact, participants in the active control group experienced greater benefits as a result of the intervention.

Walking speed decline in older adults is associated with elevated pro-BDNF in plasma extracellular vesicles

BACKGROUND

Brain-derived neurotrophic factor (BDNF) is produced by cleavage of proBDNF, and BDNF and proBDNF may play antagonistic roles in nervous system development, learning, memory and neuronal stress resistance. BDNF and proBDNF are present in blood, but the origin and relative contributions of soluble and extracellular vesicle (EV)-associated levels are unknown.

METHODS

In this study we used validated immunoassays to measure proBDNF and BDNF levels in plasma, total plasma EVs and a subpopulation of EVs enriched for neuronal origin (expressing the neuronal marker L1CAM) in 150 Baltimore Longitudinal Study of Aging participants with and without decline in walking speed (reflecting aging-associated motor decline).

RESULTS

Levels of BDNF and proBDNF were highest in L1CAM+ EVs. Participants with walking speed decline had higher levels of proBDNF in L1CAM+ EVs compared to non-decliners, but no differences in proBDNF levels in plasma and total EV.

CONCLUSIONS

Our findings suggest that levels of proBDNF and BDNF in circulating L1CAM+ EVs might be used as biomarkers for conditions involving altered BDNF signaling.

Have Standard Tests of Cognitive Function Been Misappropriated in the Study of Cognitive Enhancement?

In the past decade, there has emerged a vast research literature dealing with attempts to harness brain plasticity in older adults, with a view to improving cognitive function. Since cognitive training (CT) has shown restricted utility in this regard, attention has increasingly turned to interventions that use adjunct procedures such as motor training or physical activity (PA). As evidence builds that these have some efficacy, it becomes necessary to ensure that the outcome measures being used to infer causal influence upon cognitive function are subjected to appropriate critical appraisal. It has been highlighted previously that the choice of specific tasks used to demonstrate transfer to the cognitive domain is of critical importance. In the context of most intervention studies, standardized tests and batteries of cognitive function are de rigueur. The argument presented here is that the latent constructs to which these tests relate are not usually subject to a sufficient level of analytic scrutiny. We present the historical origins of some exemplar tests, and give particular consideration to the limits on explanatory scope that are implied by their composition and the nature of their deployment. In addition to surveying the validity of these tests when used to appraise intervention-related changes in cognitive function, we also consider their neurophysiological correlates. In particular, we argue that the broadly distributed brain activity associated with the performance of many tests of cognitive function, extending to the classical motor networks, permits the impact of interventions based on motor training or PA to be better understood.