Sex-specific relationships between obesity, physical activity, and gray and white matter volume in cognitively unimpaired older adults.

Independently, obesity and physical activity (PA) influence cerebral structure in aging, yet their interaction has not been investigated. We examined sex differences in the relationships among PA, obesity, and cerebral structure in aging with 340 participants who completed magnetic resonance imaging (MRI) acquisition to quantify grey matter volume (GMV) and white matter volume (WMV). Height and weight were measured to calculate body mass index (BMI). A PA questionnaire was used to estimate weekly Metabolic Equivalents. The relationships between BMI, PA, and their interaction on GMV Regions of Interest (ROIs) and WMV ROIs were examined. Increased BMI was associated with higher GMV in females, an inverse U relationship was found between PA and GMV in females, and the interaction indicated that regardless of BMI greater PA was associated with enhanced GMV. Males demonstrated an inverse U shape between BMI and GMV, and in males with high PA and had normal weight demonstrated greater GMV than normal weight low PA revealed by the interaction. WMV ROIs had a linear relationship with moderate PA in females, whereas in males, increased BMI was associated with lower WMV as well as a positive relationship with moderate PA and WMV. Males and females have unique relationships among GMV, PA and BMI, suggesting sex-aggregated analyses may lead to biased or non-significant results. These results suggest higher BMI, and PA are associated with increased GMV in females, uniquely different from males, highlighting the importance of sex-disaggregated models. Future work should include other imaging parameters, such as perfusion, to identify if these differences co-occur in the same regions as GMV.

Mastering the Relationship between the Body and the Brain? The Case of a Female Master Athlete.

BACKGROUND: Physical inactivity significantly increases risk of cardiovascular diseases, which are highly prevalent in aging. Conversely, higher levels of physical activity in aging have been associated with benefits for physical and cognitive health and is hypothesized to prevent and reduce development of cardiovascular risk factors. However, those older adults with the highest activity levels (i.e., Master Athletes [MA]) are relatively understudied, and even fewer studies involve female MA. OBJECTIVE: The aim of this study was to compare the physiological, physical, and cognitive profiles of an 83-year-old track-and-field MA runner to a sample of inactive age-matched females. RESULTS: Results revealed the MA had a high peak oxygen uptake and had superior performance on visuospatial memory tasks compared to her inactive counterparts. Cerebral blood flow was slightly elevated in the MA, but lower cerebrovascular reactivity was revealed compared to the other female included in the magnetic resonance imaging portion. CONCLUSION: Our results suggest that high levels of physical activity have benefits on multiple aspects of an aging female's life and that more studies should include MA, as well as a spectrum of cardiorespiratory fitness to further understand the role of physical activity in female aging.

Multiple routes to help you roam: A comparison of training interventions to improve cognitive-motor dual-tasking in healthy older adults.

Cognitive-motor dual-tasking is a complex activity that predicts falls risk and cognitive impairment in older adults. Cognitive and physical training can both lead to improvements in dual-tasking; however, less is known about what mechanisms underlie these changes. To investigate this, 33 healthy older adults were randomized to one of three training arms: Executive function (EF; n = 10), Aerobic Exercise (AE; n = 10), Gross Motor Abilities (GMA; n = 13) over 12 weeks (1 h, 3×/week). Single and dual-task performance (gait speed, m/s; cognitive accuracy, %) was evaluated before and after training, using the 2-back as concurrent cognitive load. Training arms were designed to improve cognitive and motor functioning, through different mechanisms (i.e., executive functioning - EF, cardiorespiratory fitness - CRF, and energy cost of walking - ECW). Compared to baseline, we observed few changes in dual-task gait speed following training (small effect). However, dual-task cognitive accuracy improved significantly, becoming facilitated by walking (large effect). There were no differences in the magnitude of improvements across training arms. We also found that older adults with lower cognitive ability (i.e., MoCA score < 26; n = 14) improved more on the dual-task cognitive accuracy following training, compared to older adults with higher cognitive ability (i.e., MoCA ≥26; n = 18). Taken together, the results suggest that regardless of the type of intervention, training appears to strengthen cognitive efficiency during dual-tasking, particularly for older adults with lower baseline cognitive status. These gains appear to occur via different mechanisms depending on the form of intervention. Implications of this research are paramount, as we demonstrate multiple routes for improving cognitive-motor dual-tasking in older adults, which may help reduce risk of cognitive impairment.

A Comparison of the Effect of Physical Activity and Cognitive Training on Dual-Task Performance in Older Adults.

OBJECTIVES: Studies suggest that cognitive training and physical activity can improve age-related deficits in dual-task performances. However, both of these interventions have never been compared in the same study. This article investigates the improvement in dual-task performance in 2 types of exercise training groups and a cognitive training group and explores if there are specific dual-task components that are more sensitive or more likely to improve following each type of training. METHODS: Seventy-eight healthy inactive participants older than the age of 60 (M = 69.98, SD = 5.56) were randomized to one of three 12-week training programs: aerobic training (AET) = 26, gross motor abilities (GMA) = 27, and cognition (COG) = 25. Before and after the training program, the participants underwent physical fitness tests, and cognitive evaluations involving a computerized cognitive dual task. The AET consisted of high- and low-intensity aerobic training, the GMA of full-body exercises focusing on agility, balance, coordination, and stretching, and the COG of tablet-based exercises focusing on executive functions. RESULTS: Repeated-measures analysis of variance on reaction time data revealed a group × time interaction (F(2,75) = 11.91, p < .01) with COG having the greatest improvement, followed by a significant improvement in the GMA group. Secondary analysis revealed the COG to also improve the intraindividual variability in reaction time (F(1,24) = 8.62, p < .01), while the GMA improved the dual-task cost (F(1,26) = 12.74, p < .01). DISCUSSION: The results show that physical and cognitive training can help enhance dual-task performance by improving different aspects of the task, suggesting that different mechanisms are in play.

Sex moderations in the relationship between aortic stiffness, cognition, and cerebrovascular reactivity in healthy older adults.

It is well established that sex differences exist in the manifestation of vascular diseases. Arterial stiffness (AS) has been associated with changes in cerebrovascular reactivity (CVR) and cognitive decline in aging. Specifically, older adults with increased AS show a decline on executive function (EF) tasks. Interestingly, the relationship between AS and CVR is more complex, where some studies show decreased CVR with increased AS, and others demonstrate preserved CVR despite higher AS. Here, we investigated the possible role of sex on these hemodynamic relationships. Acquisitions were completed in 48 older adults. Pseudo-continuous arterial spin labeling (pCASL) data were collected during a hypercapnia challenge. Aortic pulse wave velocity (PWV) data was acquired using cine phase contrast velocity series. Cognitive function was assessed with a comprehensive neuropsychological battery, and a composite score for EF was calculated using four cognitive tests from the neuropsychological battery. A moderation model test revealed that sex moderated the relationship between PWV and CVR and PWV and EF, but not between CVR and EF. Together, our results indicate that the relationships between central stiffness, cerebral hemodynamics and cognition are in part mediated by sex.

Comparing the effect of cognitive vs. exercise training on brain MRI outcomes in healthy older adults: A systematic review.

Aging is associated with cognitive decline. Importantly cognition and cerebral health is enhanced with interventions like cognitive (CT) and exercise training (ET). However, effects of CT and ET interventions on brain magnetic resonance imaging outcomes have never been compared systematically. Here, the primary objective was to critically and systematically compare CT to ET in healthy older adults on brain MRI outcomes. A total of 38 studies were included in the final review. Although results were mixed, patterns were identified: CT showed improvements in white matter microstructure, while ET demonstrated macrostructural enhancements, and both demonstrated changes to task-based BOLD signal changes. Importantly, beneficial effects for cognitive and cerebral outcomes were observed by almost all, regardless of intervention type. Overall, it is suggested that future work include more than one MRI outcome, and report all results including null. To better understand the MRI changes associated with CT or ET, more studies explicitly comparing interventions within the same domain (i.e. resistance vs. aerobic) and between domains (i.e. CT vs. ET) are needed.

A comparison of physical exercise and cognitive training interventions to improve determinants of functional mobility in healthy older adults.

OBJECTIVES: Mobility is a complex but crucial clinical outcome in older adults. Past observational studies have highlighted that cardiorespiratory fitness (CRF), energy cost of walking (ECW), and cognitive switching abilities are associated with mobility performance, making these key determinants of mobility intervention targets to enhance mobility in older adults. The objective of this study was to compare, in the same design, the impact of three training methods - each known to improve either CRF, ECW, or cognitive switching abilities - on mobility in healthy older adults. METHODS: Seventy-eight participants (69.28 ± 4.85yo) were randomly assigned to one of three twelve-week interventions: Aerobic Exercise (AE; n = 26), Gross Motor Abilities (GMA; n = 27), or Cognitive (COG; n = 25) training. Each intervention was designed to improve one of the three key determinants of mobility (CRF, ECW, and cognitive switching). Primary outcomes (usual gait speed, and TUG performance) and the three mobility determinants were measured before and after the intervention. RESULTS: Repeated-measures ANOVAs showed a time effect for TUG performance (F(1,75) = 14.92, p < .001): all groups equally improved after the intervention (ΔTUGpost-pre, in seconds, with 95% CI: AE = -0.44 [-0.81 to -0.08]; GMA = -0.60 [-1.10 to -0.10]; COG = -0.33 [-0.71 to 0.05]). No significant between group differences were observed. CRF was improved in the AE group only (Hedges' G = 0.27, small effect), ECW and cognitive switching improved the most in the GMA (Hedges' G = -0.78, moderate effect) and COG groups (Hedges' G = -1.93, large effect) respectively. Smaller improvements in ECW were observed following AE and COG trainings (Hedges' G: AE = -0.39, COG = -0.36, both small effects) as well as in cognitive switching following AE and GMA training (Hedges' G: AE = -0.42, GMA = -0.21, both small effects). DISCUSSION: This study provides further support to the notion that multiple interventional approaches (aerobic, gross motor exercise, or cognitive training) can be employed to improve functional mobility in older adults, giving them, and professionals, more options to promote healthy ageing.

Sensory focused exercise improves anxiety in Parkinson's disease: A randomized controlled trial.

Anxiety has been implicated as one of the greatest influences on quality of life in Parkinson's disease (PD). The etiology of anxiety is unclear, although previous work suggests that anxiety may be linked to sensory deficits that cause uncertainty in movement. Thus, the current study examined whether focusing attention on sensory feedback during goal-based exercise has the potential to provide benefits to anxiety in PD. Thirty-five participants with PD were randomized to either a Sensory Attention Focused Exercise (SAFEx) (i.e. internal focus of attention, n = 18) or Sham Exercise control (i.e. external focus of attention, n = 17) and completed 33 one-hour attention-based exercise sessions over 11-weeks. Before and after the program (pre and post), participants completed the Parkinson Anxiety Scale (PAS) questionnaire. The PAS includes three anxiety sections: persistent, episodic, and avoidance. Changes in the total PAS score and within each section of the PAS were subjected to two-factor mixed repeated measures ANCOVA. Significant group by time interactions demonstrated that from pre to post, total PAS scores (p = 0.007) and episodic anxiety scores (p = 0.010) significantly decreased in the SAFEx group only (ΔTotal PAS = -5.2, F(1,27) = 5.41, p = 0.028, ηp2 = 0.17; ΔEpisodic Score = -1.8, F(1,27) = 6.89, p = 0.014, ηp2 = 0.20). In conclusion, focusing attention on sensory feedback while completing goal-based exercises may provide significant benefits to improving anxiety in PD. As such, sensory attention focused exercise may be a critical adjunct therapy for improving anxiety, and ultimately quality of life in people with PD.

Higher cardiovascular fitness level is associated with lower cerebrovascular reactivity and perfusion in healthy older adults.

Aging is accompanied by vascular and structural changes in the brain, which include decreased grey matter volume (GMV), cerebral blood flow (CBF), and cerebrovascular reactivity (CVR). Enhanced fitness in aging has been related to preservation of GMV and CBF, and in some cases CVR, although there are contradictory relationships reported between CVR and fitness. To gain a better understanding of the complex interplay between fitness and GMV, CBF and CVR, the present study assessed these factors concurrently. Data from 50 participants, aged 55 to 72, were used to derive GMV, CBF, CVR and VO2peak. Results revealed that lower CVR was associated with higher VO2peak throughout large areas of the cerebral cortex. Within these regions lower fitness was associated with higher CBF and a faster hemodynamic response to hypercapnia. Overall, our results indicate that the relationships between age, fitness, cerebral health and cerebral hemodynamics are complex, likely involving changes in chemosensitivity and autoregulation in addition to changes in arterial stiffness. Future studies should collect other physiological outcomes in parallel with quantitative imaging, such as measures of chemosensitivity and autoregulation, to further understand the intricate effects of fitness on the aging brain, and how this may bias quantitative measures of cerebral health.

State anxiety predicts cognitive performance in patients with Parkinson's disease.

OBJECTIVE: Anxiety is common in Parkinson's disease (PD) and frequently a comorbidity that appears alongside nonmotor symptoms such as cognitive deficits; however, the relationship between anxiety and cognition in PD remains poorly understood. The aim of this study was to investigate the relationship between anxiety and specific cognitive domains (e.g., attention/working memory, executive functions, memory, language, and visuospatial function). METHOD: A total of 48 individuals with PD and 18 healthy controls were assessed using the State Trait Anxiety Inventory along with a comprehensive neuropsychological battery. Hierarchical multiple regression analysis was used to examine whether trait and/or state anxiety predicted deficits in overall cognitive function (Montreal Cognitive Assessment) and/or specific individual cognitive domains in the PD and healthy control samples while controlling for covariates such as age, depression (Geriatric Depression Scale), and Unified Parkinson's disease Rating Scale motor-subsection-III (PD only). RESULTS: Results showed that state anxiety in PD significantly predicted performance across an array of cognitive domains, such as attention/working memory, executive functioning, memory, and language, whereas trait anxiety was a predictor only for executive functioning. In contrast, there was no significant relationship between state anxiety and visuospatial ability Conclusions: Overall, these findings highlight that performance in particular cognitive domains are associated with anxiety in PD. Thus, it may be critically important to consider and quantify the contribution of anxiety to cognitive performance when diagnosing and treating dementia and/or mild cognitive impairments in PD. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The effects of exercise on cognition and gait in Parkinson's disease: A scoping review.

Cognitive and gait deficits are two debilitating symptoms that occur in Parkinson's disease (PD). Importantly, a relationship between cognitive and gait deficits exists in PD, suggesting reliance on cognition is increased to compensate for gait deficits and/or deterioration of cognition and gait may share common mechanisms. Rehabilitation strategies targeting one factor could lead to the improvement of the other, presenting a unique opportunity to treat both simultaneously. Gold-standard pharmaceuticals partially alleviate these deficits with significant side effects, highlighting the importance of investigating adjunct therapies like exercise. We critically reviewed the influence of three exercise modalities (aerobic, resistance, and goal-based) on cognition and/or gait in PD. Most studies showed improvements in cognition or gait, yet, a limited number investigated them concurrently. This is the first review examining exercise for cognition and gait in PD. Key gaps in the literature are identified; potential exercise-driven mechanisms for enhancements in cognition and gait proposed, and suggestions for the design of future studies investigating the effects of exercise on cognition and gait in PD.

Aerobic exercise is more effective than goal-based exercise for the treatment of cognition in Parkinson's disease.

BACKGROUND: Little is known about how different exercise modalities influence cognition in Parkinson's disease (PD). Moreover, the focus of previous investigations on examining the effects of exercise mainly on executive functions and the exclusion of individuals with cognitive impairment may limit the potential to define exercise as a treatment for cognitive decline in PD. OBJECTIVE: The aim of this study was to compare the effects of aerobic and goal-based exercise on five cognitive domains in cognitively normal and impaired individuals with PD. METHODS: Seventy-six individuals with PD were randomly allocated into three groups: Aerobic, Goal-based, and Control. Participants in the exercise groups attended 1-h sessions 3x/week for 12 weeks, while those in the Control group carried on with their regular activities. Changes in cognitive domains were assessed using paper-based neuropsychological tests. RESULTS: Inhibitory control improved only in the Aerobic group (p = .04), irrespective of participants cognitive status at baseline. Moreover, participants with cognitive impairment in Aerobic group maintained their set-shifting ability, whereas those in the Control group were worse at post-test (p = .014). CONCLUSION: This is the first study to show that aerobic exercise is more effective than goal-based exercise for the treatment of cognition in PD with and without cognitive impairment.

Can Dual Task Walking Improve in Parkinson's Disease After External Focus of Attention Exercise? A Single Blind Randomized Controlled Trial.

BACKGROUND: It may be possible to use attention-based exercise to decrease demands associated with walking in Parkinson's disease (PD), and thus improve dual task walking ability. For example, an external focus of attention (focusing on the effect of an action on the environment) may recruit automatic control processes degenerated in PD, whereas an internal focus (limb movement) may recruit conscious (nonautomatic) control processes. Thus, we aimed to investigate how externally and internally focused exercise influences dual task walking and symptom severity in PD. METHODS: Forty-seven participants with PD were randomized to either an Externally (n = 24) or Internally (n = 23) focused group and completed 33 one-hour attention-based exercise sessions over 11 weeks. In addition, 16 participants were part of a control group. Before, after, and 8 weeks following the program (pre/post/washout), gait patterns were measured during single and dual task walking (digit-monitoring task, ie, walking while counting numbers announced by an audio-track), and symptom severity (UPDRS-III) was assessed ON and OFF dopamine replacement. Pairwise comparisons (95% confidence intervals [CIs]) and repeated-measures analyses of variance were conducted. RESULTS: Pre to post: Dual task step time decreased in the external group (Δ = 0.02 seconds, CI 0.01-0.04). Dual task step length (Δ = 2.3 cm, CI 0.86-3.75) and velocity (Δ = 4.5 cm/s, CI 0.59-8.48) decreased (became worse) in the internal group. UPDRS-III scores (ON and OFF) decreased (improved) in only the External group. Pre to washout: Dual task step time ( P = .005) and percentage in double support ( P = .014) significantly decreased (improved) in both exercise groups, although only the internal group increased error on the secondary counting task (ie, more errors monitoring numbers). UPDRS-III scores in both exercise groups significantly decreased ( P = .001). CONCLUSIONS: Since dual task walking improvements were found immediately, and 8 weeks after the cessation of an externally focused exercise program, we conclude that externally focused exercise may improve on functioning of automatic control networks in PD. Internally focused exercise hindered dual tasking ability. Overall, externally focused exercise led to greater rehabilitation benefits in dual tasking and motor symptoms compared with internally focused exercise.

Overload From Anxiety: A Non-Motor Cause for Gait Impairments in Parkinson's Disease.

Threatening situations lead to observable gait deficits in individuals with Parkinson's disease (PD) who suffer from high trait anxiety levels. The specific characteristics of gait that are affected appear to be similar to behaviors observed while walking during a dual-task (DT) condition. Yet, it remains unclear whether anxiety is similar to a cognitive load. If it were, then those with PD who have high trait anxiety might be expected to be more susceptible to DT interference during walking. Thus, the overall aim of this study was to evaluate whether trait anxiety influences gait during single-task (ST) and DT walking. Seventy participants (high-anxiety PD [HA-PD], N=26; low-anxiety PD [LA-PD], N=26; healthy control [HC], N=18) completed three ST and three DT walking trials on a data-collecting carpet. The secondary task consisted of digit monitoring while walking. Results showed that during both ST and DT gait, the HA-PD group demonstrated significant reductions in walking speed and step length, as well as increased step length variability and step time variability compared with healthy controls and the LA-PD group. Notably, ST walking in the HA-PD group resembled (i.e., it was not significantly different from) the gait behaviors seen during a DT in the LA-PD and HC groups. These results suggest that trait anxiety may consume processing resources and limit the ability to compensate for gait impairments in PD.

Changes in Physical Activity and Function with Transition to Retirement Living: A Pilot Study.

This pilot study examined changes in physical activity and function among older adults moving from community dwellings to retirement living. Twelve community-dwelling older adults, recruited from the wait-lists of two retirement living facilities, were assessed prior to and following the transition to retirement living. Physical activity was assessed using an Actigraph (GT3X+) activity monitor; physical activity by type was reported with the CHAMPS activity questionnaire. Physical function was assessed using the Senior Fitness Test. Objectively monitored total physical activity decreased after the transition to retirement living (p = 0.02). Reports of physical activity by type indicated that only activities of daily living decreased (p < 0.01) although intentional exercise increased (p < 0.03) with the transition. Endurance and strength also improved (p < 0.05 and p < 0.04). Pilot results indicate that possible physical benefits accrue from retirement living, although efforts to reduce sedentary time are needed.

Is Cardiac Rehabilitation Exercise Feasible for People with Mild Cognitive Impairment?

BACKGROUND: Exercise is a promising strategy to prevent dementia, but no clinically supervised exercise program is widely available to people with mild cognitive impairment (MCI). The objective was to survey health professionals to assess the feasibility of using cardiac rehabilitation exercise programs for MCI populations. METHODS: We distributed surveys to: 1) health professionals working in cardiac rehabilitation exercise programs (36/72 responded); and 2) physicians who treat MCI (22/32 responded). Questions addressed clinician and clinic characteristics and feasibility of referring and accommodating people with MCI. RESULTS: Most cardiac rehabilitation exercise programs currently treat people with MCI (61.1%). Nearly all were willing and able to accept people with MCI and comorbid vascular risk (91.7%), though only a minority could accept MCI without vascular risk (16.7%). Although most physicians recommend exercise to people with MCI (63.6%), few referred patients with MCI to programs or people to guide exercise (27.3%). However, all physicians (100%) would refer patients with MCI to a cardiac rehabilitation exercise program. CONCLUSIONS: Our study supports cardiac rehabilitation exercise programs as a feasible model of exercise for patients with MCI with vascular risk. Patients with and without vascular risk could likely be accommodated if program mandates were expanded.

Information Seeking in Social Media: A Review of YouTube for Sedentary Behavior Content.

BACKGROUND: The global prevalence of sedentary lifestyles is of grave concern for public health around the world. Moreover, the health risk of sedentary behaviors is of growing interest for researchers, clinicians, and the general public as evidence demonstrates that prolonged amounts of sedentary time increases risk for lifestyle-related diseases. There is a growing trend in the literature that reports how social media can facilitate knowledge sharing and collaboration. Social sites like YouTube facilitate the sharing of media content between users. OBJECTIVE: The purpose of this project was to identify sedentary behavior content on YouTube and describe features of this content that may impact the effectiveness of YouTube for knowledge translation. METHODS: YouTube was searched on a single day by 3 independent reviewers for evidence-based sedentary behavior content. Subjective data (eg, video purpose, source, and activity type portrayed) and objective data (eg, number of views, comments, shares, and length of the video) were collected from video. RESULTS: In total, 106 videos met inclusion criteria. Videos were uploaded from 13 countries around the globe (ie, Australia, Barbados, Belgium, Canada, Colombia, Kenya, New Zealand, Russia, South Africa, Spain, Ukraine, United Kingdom, United States). The median video length was 3:00 minutes: interquartile range (IQR) 1:44-5:40. On average, videos had been on YouTube for 15.0 months (IQR 6.0-27.5) and had been viewed 239.0 times (IQR 44.5-917.5). Videos had remarkably low numbers of shares (median 0) and comments (median 1). Only 37.7% (40/106) of videos portrayed content on sedentary behaviors, while the remaining 66 videos portrayed physical activity or a mix of behaviors. Academic/health organizations (39.6%, 42/106) and individuals (38.7%, 41/106) were the most prevalent source of videos, and most videos (67.0%, 71/106) aimed to educate viewers about the topic. CONCLUSIONS: This study explored sedentary behavior content available on YouTube. Findings demonstrate that there is confusion between physical activity and sedentary behaviors, that content is being uploaded to the site from around the globe, that content is primarily from health organizations and individuals with the purpose of educating fellow users, but that low views, comments, and shares suggest that sedentary behavior content is relatively underutilized on YouTube. Future research may wish to leverage social platforms, such as YouTube, to facilitate implementation and sharing of evidence-based sedentary behavior content.