Cardiac hemodynamics phenotypes and individual responses to training in coronary heart disease patients.

BACKGROUND: In patients with coronary heart disease (CHD), individualized exercise training (ET) programs are strongly recommended to optimize peak oxygen uptake ( V ̇ $$ \dot{\mathrm{V}} $$ O2peak) improvement and prognosis. However, the cardiac hemodynamic factors responsible for a positive response to training remain unclear. The aim of this study was to compare cardiac hemodynamic changes after an ET program in responder (R) versus non-responder (NR) CHD patients. METHODS: A total of 72 CHD patients completed a 3-month ET program and were assessed by cycle ergometer cardiopulmonary exercise test (CPET: V ̇ $$ \dot{\mathrm{V}} $$ O2peak assessment) with impedance cardiography (ICG) for hemodynamic measurements before and after training. Cardiac hemodynamics (e.g., CO, CI, SV, ESV, EDV, and SVR) were measured by ICG during CPET. The R and NR groups were classified using the median change in V ̇ $$ \dot{\mathrm{V}} $$ O2peak (>the median for R and ≤the median for NR). RESULTS: In the R group, V ̇ $$ \dot{\mathrm{V}} $$ O2peak (+17%, p < 0.001), CO, CI, SV, and HR increased by 17%, 17%, 13%, and 5%, respectively (p < 0.05) after the training program. In the NR group, V ̇ $$ \dot{\mathrm{V}} $$ O2peak, CO, CI, and SV increased by 0.5%, 5%, 8%, and 6%, respectively (p < 0.01). The SVR decreased in both groups (-19% in R and -11% in NR, p < 0.001). CONCLUSION: Among CHD patients, the R group showed a better improvement in peak cardiac output via an increase in peak stroke volume and heart rate and a reduced systemic vascular resistance than the NR group. Different cardiac phenotype adaptations and clinical individual responses were identified in CHD patients according to the aerobic fitness responder's status.

Determinants of V̇+O2peak Changes After Aerobic Training in Coronary Heart Disease Patients.

This study aimed to highlight the ventilatory and circulatory determinants of changes in ˙VO2peak after exercise-based cardiac rehabilitation (ECR) in patients with coronary heart disease (CHD). Eighty-two CHD patients performed, before and after a 3-month ECR, a cardiopulmonary exercise testing (CPET) on a bike with gas exchanges measurements (˙VO2peak, minute ventilation, i. e., ˙VE), and cardiac output (Q˙c). The arteriovenous difference in O2 (C(a-v¯)O2) and the alveolar capillary gradient in O2 (PAi-aO2) were calculated using Fick's laws. Oxygen uptake efficiency slope (OUES) was calculated. A 5.0% cut off was applied for differentiating non- (NR: ˙VO2<0.0%), low (LR: 0.0≤ ∆˙VO2<5.0%), moderate (MR: 5.0≤∆˙VO2 < 10.0%), and high responders (HR: ∆˙VO2≥10.0%) to ECR. A total of 44% of patients were HR (n=36), 20% MR (n=16), 23% LR (n=19), and 13% NR (n=11). For HR, the ˙VO2peak increase (p<0.01) was associated with increases in ˙VE (+12.8±13.0 L/min, p<0.01), (+1.0±0.9 L/min, p<0.01), and C(a-v¯)O2 (+2.3±2.5 mLO2/100 mL, p<0.01). MR patients were characterized by+6.7±19.7 L/min increase in ˙VE (p=0.04) and+0.7±1.0 L/min of Q˙c (p<0.01). ECR induced decreases in ˙VE (p=0.04) and C(a-v¯)O2 (p<0.01) and a Q˙c increase in LR and NR patients (p<0.01). Peripheral and ventilatory responses more than central adaptations could be responsible for the ˙VO2peak change with ECR in CHD patients.

Cardiopulmonary rehabilitation's influence on cognitive functions, psychological state, and sleep quality in long COVID-19 patients: A randomized controlled trial.

CLINICALTRIALS.GOV: NCT05035628.Trial registration: ClinicalTrials.gov identifier: NCT05035628..

At-home computerized executive-function training to improve cognition and mobility in normal-hearing adults and older hearing aid users: a multi-centre, single-blinded randomized controlled trial.

BACKGROUND: Hearing loss predicts cognitive decline and falls risk. It has been argued that degraded hearing makes listening effortful, causing competition for higher-level cognitive resources needed for secondary cognitive or motor tasks. Therefore, executive function training has the potential to improve cognitive performance, in turn improving mobility, especially when older adults with hearing loss are engaged in effortful listening. Moreover, research using mobile neuroimaging and ecologically valid measures of cognition and mobility in this population is limited. The objective of this research is to examine the effect of at-home cognitive training on dual-task performance using laboratory and simulated real-world conditions in normal-hearing adults and older hearing aid users. We hypothesize that executive function training will lead to greater improvements in cognitive-motor dual-task performance compared to a wait-list control group. We also hypothesize that executive function training will lead to the largest dual-task improvements in older hearing aid users, followed by normal-hearing older adults, and then middle-aged adults. METHODS: A multi-site (Concordia University and KITE-Toronto Rehabilitation Institute, University Health Network) single-blinded randomized controlled trial will be conducted whereby participants are randomized to either 12 weeks of at-home computerized executive function training or a wait-list control. Participants will consist of normal-hearing middle-aged adults (45-60 years old) and older adults (65-80 years old), as well as older hearing aid users (65-80 years old, ≥ 6 months hearing aid experience). Separate samples will undergo the same training protocol and the same pre- and post-evaluations of cognition, hearing, and mobility across sites. The primary dual-task outcome measures will involve either static balance (KITE site) or treadmill walking (Concordia site) with a secondary auditory-cognitive task. Dual-task performance will be assessed in an immersive virtual reality environment in KITE's StreetLab and brain activity will be measured using functional near infrared spectroscopy at Concordia's PERFORM Centre. DISCUSSION: This research will establish the efficacy of an at-home cognitive training program on complex auditory and motor functioning under laboratory and simulated real-world conditions. This will contribute to rehabilitation strategies in order to mitigate or prevent physical and cognitive decline in older adults with hearing loss. TRIAL REGISTRATION: Identifier: NCT05418998. https://clinicaltrials.gov/ct2/show/NCT05418998.

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.

Exploring cognitive and brain oxygenation changes over a 1-year period in physically active individuals with mild cognitive impairment: a longitudinal fNIRS pilot study.

BACKGROUND: Aging is associated with an increased likelihood of developing dementia, but a growing body of evidence suggests that certain modifiable risk factors may help prevent or delay dementia onset. Among these, physical activity (PA) has been linked to better cognitive performance and brain functions in healthy older adults and may contribute to preventing dementia. The current pilot study investigated changes in behavioral and brain activation patterns over a 1-year period in individuals with mild cognitive impairment (MCI) and healthy controls taking part in regular PA. METHODS: Frontal cortical response during a dual-task walking paradigm was investigated at baseline, at 6 months (T6), and at 12 months (T12) by means of a portable functional Near-Infrared Spectroscopy (fNIRS) system. The dual-task paradigm included a single cognitive task (2-back), a single motor task (walking), and a dual-task condition (2-back whilst walking). RESULTS: Both groups showed progressive improvement in cognitive performance at follow-up visits compared to baseline. Gait speed remained stable throughout the duration of the study in the control group and increased at T6 for those with MCI. A significant decrease in cortical activity was observed in both groups during the cognitive component of the dual-task at follow-up visits compared to baseline, with MCI individuals showing the greatest improvement. CONCLUSIONS: The observations of this pilot study suggest that taking part in regular PA may be especially beneficial for both cognitive performance and brain functions in older adulthood and, especially, in individuals with MCI. Our findings may serve as preliminary evidence for the use of PA as a potential intervention to prevent cognitive decline in individuals at greater risk of dementia.

Videoconference version of the Montreal Cognitive Assessment: normative data for Quebec-French people aged 50 years and older.

BACKGROUND: The COVID-19 pandemic forced health professionals to rapidly develop and implement telepractice and remote assessments. Recent reviews appear to confirm the validity of a wide range of neuropsychological tests for teleneuropsychology and among these, the Montreal Cognitive Assessment (MoCA), a cognitive screening test widely used in clinical settings. The normative data specific to the context of videoconference administration is essential, particularly that consider sociodemographic characteristics. AIMS: This study had for objective to develop French-Quebec normative data for videoconference-administration of the MoCA that consider sociodemographic characteristics. METHODS: A total of 230 community-dwelling adults aged 50 years and older taking part in clinical trials completed the MoCA by videoconference. Regression analyses were run with sex, education, and age as predictors of the total MoCA scores, based on previously published norms. As an exploratory analysis, a second regression analysis was also run with cardiovascular disease as a predictor. RESULTS: Regression analyses revealed that older age and lower education were associated with poorer total MoCA scores, for medium effect size (p < 0.001, R2 = 0.17). Neither sex nor cardiovascular disease, were significant predictors in our analyses. For clinicians, a regression equation was proposed to calculate Z scores. DISCUSSION: This study provides normative data for the MoCA administered via videoconference in Quebec-French individuals aged 50 years and over. CONCLUSIONS: The present normative data will not only allow clinicians to continue to perform assessments remotely in this pandemic period but will also allow them to perform cognitive assessments to patients located in remote areas.

Coronary artery disease and its impact on the pulsatile brain: A functional NIRS study.

Recent studies have reported that optical indices of cerebral pulsatility are associated with cerebrovascular health in older adults. Such indices, including cerebral pulse amplitude and the pulse relaxation function (PRF), have been previously applied to quantify global and regional cerebral pulsatility. The aim of the present study was to determine whether these indices are modulated by cardiovascular status and whether they differ between individuals with low or high cardiovascular risk factors (LCVRF and HCVRF) and coronary artery disease (CAD). A total of 60 older adults aged 57-79 were enrolled in the study. Participants were grouped as LCVRF, HCVRF, and CAD. Participants were asked to walk freely on a gym track while a near-infrared spectroscopy (NIRS) device recorded hemodynamics data. Low-intensity, short-duration walking was used to test whether a brief cardiovascular challenge could increase the difference of pulsatility indices with respect to cardiovascular status. Results indicated that CAD individuals have higher global cerebral pulse amplitude compared with the other groups. Walking reduced global cerebral pulse amplitude and PRF in all groups but did not increase the difference across the groups. Instead, walking extended the spatial distribution of cerebral pulse amplitude to the anterior prefrontal cortex when CAD was compared to the CVRF groups. Further research is needed to determine whether cerebral pulse amplitude extracted from data acquired with NIRS, which is a noninvasive, inexpensive method, can provide an index to characterize the cerebrovascular status associated with CAD.

Cognitive performances better identify fallers than mobility assessment among older adults with fear of falling.

BACKGROUND: Half of the people with fear of falling (FoF) are non-fallers, and the reason why some people considered non-fallers are afraid of falling is unknown, but reduced mobility or cognition, or both concurrently must be considered as potential risk factors. AIM: The study aimed to determine if mobility and/or cognitive abilities could identify people with a history of falls in older adults with FoF. METHODS: Twenty-six older adults with FoF participated in this study. Full cognitive and mobility assessments were performed assessing global cognitive impairments (MoCA score < 26), executive functions, memory, processing speed, visuospatial skills, mobility impairment (TUG time > 13.5 s), gait, balance and physical capacity. Information about falls occurring during the year prior to the inclusion was collected. Logistic regression analyses were performed to explore the association between falls and cognitive and mobility abilities. RESULTS: No significant differences in age, sex, level of education or body mass index were detected between fallers and non-fallers. Cognitive impairments (MoCA score < 26) distinguished between fallers and non-fallers (p = 0.038; R2 = 0.247). Among specific cognitive functions, visuospatial skills distinguished between fallers and non-fallers (p = 0.027; R2 = 0.258). Mobility impairments (TUG time > 13.5 s), gait, balance and physical capacity were not related to past falls. DISCUSSION/CONCLUSION: In older adults with FoF, global cognitive deficits detected by the MoCA are important factors related to falls and more particularly visuospatial skills seem to be among the most implicated functions. These functions could be targeted in multifactorial interventions.

Gait variability across neurodegenerative and cognitive disorders: Results from the Canadian Consortium of Neurodegeneration in Aging (CCNA) and the Gait and Brain Study.

INTRODUCTION: Gait impairment is common in neurodegenerative disorders. Specifically, gait variability-the stride-to-stride fluctuations in distance and time-has been associated with neurodegeneration and cognitive impairment. However, quantitative comparisons of gait impairments across the cognitive spectrum of dementias have not been systematically investigated. METHODS: Older adults (N = 500) with subjective cognitive impairment, Parkinson disease (PD), mild cognitive impairment (MCI), PD-MCI, Alzheimer's disease (AD), PD-dementia, Lewy body dementia, and frontotemporal dementia, as well cognitive normal controls, who were assessed for their gait and cognitive performance. RESULTS: Factor analyses grouped 11 quantitative gait parameters and identified four independent gait domains: rhythm, pace, variability, and postural control, for group comparisons and classification analysis. Among these domains, only high gait variability was associated with lower cognitive performance and accurately discriminated AD from other neurodegenerative and cognitive conditions. DISCUSSION: Our findings indicate that high gait variability is a marker of cognitive-cortical dysfunction, which can help to identify Alzheimer's disease dementia.

Dual decline in gait speed and cognition is associated with future dementia: evidence for a phenotype.

BACKGROUND: concurrent declines in gait speed and cognition have been associated with future dementia. However, the clinical profile of 'dual decliners', those with concomitant decline in both gait speed and cognition, has not been yet described. We aimed to describe the phenotype and the risk for incident dementia of those who present with dual decline in comparison with non-dual decliners. METHODS: prospective cohort of community-dwelling older adults free of dementia at baseline. We evaluated participants' gait speed, cognition, medical status, functionality, incidence of adverse events and dementia, biannually over 7 years. Gait speed was assessed with a 6-m electronic walkway and global cognition using the MoCA test. We compared characteristics between dual decliners and non-dual decliners using t-test, chi-square and hierarchical regression models. We estimated incident dementia using Cox models. RESULTS: among 144 participants (mean age 74.23 ± 6.72 years, 54% women), 17% progressed to dementia. Dual decliners had a 3-fold risk (HR: 3.12, 95%CI: 1.23-7.93, P = 0.017) of progression to dementia compared with non-dual decliners. Dual decliners were significantly older with a higher prevalence of hypertension and dyslipidemia (P = 0.002). Hierarchical regression models show that age and sex alone explained 3% of the variation in the dual decliners group. Adding hypertension and dyslipidemia increased the explained variation by 8 and 10%, respectively. The risk of becoming a dual decliner was 4-fold higher if hypertension was present. CONCLUSION: older adults with a concurrent decline in gait speed and cognition represent a group at the highest risk of progression to dementia. Older adults with dual decline have a distinct phenotype with a higher prevalence of hypertension, a treatable condition.

Cardiac Rehabilitation During Quarantine in COVID-19 Pandemic: Challenges for Center-Based Programs.

Because of the coronavirus disease 2019 (COVID-19) epidemic, many cardiac rehabilitation (CR) services and programs are stopped. Because CR is a class I level A recommendation with clinical benefits that are now well documented, the cessation of CR programs can lead to dramatic consequences in terms of public health. We propose here a viewpoint of significant interest about the sudden need to develop remote home-based CR programs both in clinical research and in clinical care routine. This last decade, the literature on remote home-based CR programs has been increasing, but to date only clinical research experiences have been implemented. Benefits are numerous and the relevance of this approach has obviously increased with the actual health emergency. The COVID-19 crisis, the important prevalence of smartphones, and high-speed Internet during confinement should be viewed as an opportunity to promote a major shift in CR programs with the use of telemedicine to advance the health of a larger number of individuals with cardiac disease.

Arterial stiffness and white matter integrity in the elderly: A diffusion tensor and magnetization transfer imaging study.

BACKGROUND AND PURPOSE: The stiffness of large arteries and increased pulsatility can have an impact on the brain white matter (WM) microstructure, however those mechanisms are still poorly understood. The aim of this study was to investigate the association between central artery stiffness, axonal and myelin integrity in 54 cognitively unimpaired elderly subjects (65-75 years old). METHODS: The neuronal fiber integrity of brain WM was assessed using diffusion tensor metrics and magnetization transfer imaging as measures of axonal organization (Fractional anisotropy, Radial diffusivity) and state of myelination (Myelin volume fraction). Central artery stiffness was measured by carotid-femoral pulse wave velocity (cfPWV). Statistical analyses included 4 regions (the corpus callosum, the internal capsule, the corona radiata and the superior longitudinal fasciculus) which have been previously denoted as vulnerable to increased central artery stiffness. RESULTS: cfPWV was significantly associated with fractional anisotropy and radial diffusivity (p < 0.05, corrected for multiple comparisons) but not with myelin volume fraction. Findings from this study also show that improved executive function performance correlates with Fractional anisotropy positively (p < 0.05 corrected) as well as with myelin volume fraction and radial diffusivity negatively (p < 0.05 corrected). CONCLUSIONS: These findings suggest that arterial stiffness is associated with axon degeneration rather than demyelination. Controlling arterial stiffness may play a role in maintaining the health of WM axons in the aging brain.

Dance your stress away: comparing the effect of dance/movement training to aerobic exercise training on the cortisol awakening response in healthy older adults.

This study aimed to examine in healthy older adults the effects of dance/movement training (DMT) on the cortisol awakening response (CAR), a marker of chronic stress. Forty participants (mean age = 67.45, 75% women) were randomized into three groups: DMT (n = 12) - a set of exercises to promote gross motor skills, body awareness, and socialization; aerobic exercise training (AT; n = 14) - high intensity activity on a recumbent bicycle, and wait list (WL; n = 14). Both DMT and AT groups were supervised by licensed instructors and met three times a week for three months. Before and after their respective program, participants of all groups provided saliva samples on 3 d at 0-, 30- and 60-min after awakening, and had their fitness level evaluated. A significant group × time interaction (F(2,34) = 5.79, p = .01, η2partial = 0.25) was found, with the DMT group showing lower salivary cortisol values post-training, while the other two groups showed no change from baseline in their CAR. Cardiorespiratory fitness improved only in the AT group, while DMT showed no group-specific physical functioning improvements. The results are discussed in terms of the importance of physical and psychological effects of training on change in cortisol levels.

Higher cardiovascular fitness level is associated to better cognitive dual-task performance in Master Athletes: Mediation by cardiac autonomic control.

INTRODUCTION/PURPOSE: This study compared cognitive performances and cardiac autonomic measures of higher fit and lower fit middle-aged and older highly active adults. The working hypotheses were that higher fit (master athletes) would show cognitive benefits in executive control conditions due to a high level of fitness compared to lower fit people and that this effect would be mediated by better cardiac autonomic adaptations in athletes. METHODS: We recruited 39 highly active middle aged and older adults from Master Athletes' organizations. All participants performed a Rockport walking test and a computerized dual-task. Cardiac autonomic control was assessed with a measure of heart rate variability. Based on the V̇O2max estimated by the Rockport test, a median split was performed to assess the influence of fitness level on cognitive performance and the link with heart rate variability. Those with the highest fitness level were considered Master Athletes. RESULTS: Master Athletes showed better dual-task performances than lower fit individuals. A positive relationship between the V̇O2max and dual-task performances was also observed. Master Athletes demonstrated a lower resting HR and higher RR interval than lower fit individuals, and this index was specifically related to the executive conditions of the dual task. CONCLUSION: Our results highlight the role of fitness level on executive function in highly active middle aged and older adults and suggest that the better performances observed in highly fit individuals is mediated by cardiac autonomic control.

SYNERGIC TRIAL (SYNchronizing Exercises, Remedies in Gait and Cognition) a multi-Centre randomized controlled double blind trial to improve gait and cognition in mild cognitive impairment.

BACKGROUND: Physical exercise, cognitive training, and vitamin D are low cost interventions that have the potential to enhance cognitive function and mobility in older adults, especially in pre-dementia states such as Mild Cognitive Impairment (MCI). Aerobic and progressive resistance exercises have benefits to cognitive performance, though evidence is somewhat inconsistent. We postulate that combined aerobic exercise (AE) and progressive resistance training (RT) (combined exercise) will have a better effect on cognition than a balance and toning control (BAT) intervention in older adults with MCI. We also expect that adding cognitive training and vitamin D supplementation to the combined exercise, as a multimodal intervention, will have synergistic efficacy. METHODS: The SYNERGIC trial (SYNchronizing Exercises, Remedies in GaIt and Cognition) is a multi-site, double-blinded, five-arm, controlled trial that assesses the potential synergic effect of combined AE and RT on cognition and mobility, with and without cognitive training and vitamin D supplementation in older adults with MCI. Two-hundred participants with MCI aged 60 to 85 years old will be randomized to one of five arms, four of which include combined exercise plus combinations of dual-task cognitive training (real vs. sham) and vitamin D supplementation (3 × 10,000 IU/wk. vs. placebo) in a quasi-factorial design, and one arm which receives all control interventions. The primary outcome measure is the ADAS-Cog (13 and plus modalities) measured at baseline and at 6 months of follow-up. Secondary outcomes include neuroimaging, neuro-cognitive performance, gait and mobility performance, and serum biomarkers of inflammation (C reactive protein and interleukin 6), neuroplasticity (brain-derived neurotropic factor), endothelial markers (vascular endothelial growth factor 1), and vitamin D serum levels. DISCUSSION: The SYNERGIC Trial will establish the efficacy and feasibility of a multimodal intervention to improve cognitive performance and mobility outcomes in MCI. These interventions may contribute to new approaches to stabilize and reverse cognitive-mobility decline in older individuals with MCI. TRIAL REGISTRATION: Identifier: NCT02808676. https://www.clinicaltrials.gov/ct2/show/NCT02808676 .

The Effects of Multi-Component Exercise Training on Cognitive Functioning and Health-Related Quality of Life in Older Adults.

PURPOSE: Exercise has been shown to have various proximal and distal benefits among older adults such as improving physical fitness, cognitive functioning, and health-related quality of life (HR-QOL). Despite this evidence, limited research has investigated pathway change of these outcomes. The primary purpose of this study was to test if older adults who improved in physical fitness measures from engaging in multicomponent exercise training for 12 weeks predicted change in proximal (cognitive functioning) and distal (HR-QOL) outcomes, respectively. METHODS: Participants (n = 110) were healthy, older adults (M = 72, SD = 7.24) that comprised an exercise-intervention and control group. The intervention consisted of exercising in a supervised laboratory setting for 12 weeks. RESULTS: Structural equation modeling revealed group type to predict change in physical performance and the maximum walking test with comparable effect sizes. Physical performance in turn predicted improvement in processing speed (ß = 0.23, p = 0.013) executive functioning (ß = 0.26, p = 0.006), and HR-QOL (ß = 0.13, p = 0.031). However, only executive functioning was found to significantly predict HR-QOL (ß = 0.49, p < 0.001) over processing speed (p > 0.05). CONCLUSIONS: Between two fitness measures, the physical performance test demonstrated better predictive validity in proximal and distal health outcomes. In addition to physical fitness, older adults who engage in multi-component exercise sessions regularly can improve their executive functioning, which in turn enhances their HR-QOL.

A comparison of the impact of physical exercise, cognitive training and combined intervention on spontaneous walking speed in older adults.

BACKGROUND: Spontaneous walking speed (SWS) is one of the most important indicators of health in older adults. Studies have shown benefits of physical trainings on SWS in older adults but the impact of cognitive training and multidomain interventions remains understudied. AIMS: This original study aimed at comparing the impact of aerobic/resistance exercise, computerized cognitive training and the combination of both interventions compared with active control conditions on SWS in healthy older adults. METHODS: Ninety community-dwelling older adults were randomly assigned to four different combinations composed of two active interventions: physical aerobic/resistance and cognitive dual-task trainings, and two active control conditions: stretching exercises and computer lessons. The four combinations were the following: (1) aerobic/resistance and cognitive dual task (n = 28), (2) aerobic/resistance and computer lessons (n = 21), (3) stretching exercises and cognitive dual task and (n = 23), (4) stretching exercises and computer lessons (n = 18). Training sessions were held three times/week for three months. SWS for 30 s was assessed before and after the intervention. RESULTS: Repeated-measures ANOVA showed a main effect of time and a significant three-way interaction suggesting differential improvement in SWS according to training combinations. A clinical meaningful improvement in SWS was observed in groups 1-3 (0.08-0.14 m/s; effect sizes: small to moderate) but not in the active control group 4. DISCUSSION: Results of this study suggest that aerobic/resistance exercise and computerized dual-task training are two non-pharmacological interventions by which SWS, a functional vital sign, can be clinically improved in older adults. CONCLUSION: This original study pointed out different tools to prevent functional decline in older people.

Association Between Falls and Brain Subvolumes: Results from a Cross-Sectional Analysis in Healthy Older Adults.

Falls are a consequence of gait instability. Cortical and subcortical abnormalities have been associated with gait instability but not yet with falls. This study aims to compare the global and regional brain subvolumes between healthy older fallers and non-fallers. A total of 77 healthy older individuals (23 fallers and 54 non-fallers, 69.8 ± 3.5 years; 45.5 % female) were included in this study using a cross-sectional design. Based on an a priori hypothesis, the following brain subvolumes were quantified from three-dimensional T1-weighted MRI using FreeSurfer software: total white matter abnormalities, total white matter, total cortical and subcortical gray matter, hippocampus, motor cortex, somatosensory cortex, premotor cortex, prefrontal cortex and parietal cortex volumes. Gait performances were also recorded. Age, sex, body mass index, comorbidities, use of psychoactive drugs, far-distance visual acuity, lower-limb proprioception, depressive symptoms and cognitive scores (Mini-Mental State Examination, Frontal Assessment Battery) were used as covariates. Fallers have more frequently depressive symptoms (P = 0.048), a lower far distance visual acuity (P = 0.026) and a higher coefficient of variation of stride time (P = 0.008) compared to non-fallers. There was a trend to greater subvolumes for the somatosensory cortex (P = 0.093) and the hippocampus (P = 0.060) in the falls group. Multiple logistic regressions showed that subvolumes of the somatosensory cortex and the hippocampus (P < 0.042) were increased in fallers compared to non-fallers, even after adjustment for clinical and brain characteristics. The greater subvolumes of the somatosensory cortex and hippocampus reported in fallers compared to non-fallers suggests a possible brain compensatory mechanism involving spatial navigation and integration of sensory information.

Relationships between lower body strength and the energy cost of treadmill walking in a cohort of healthy older adults: a cross-sectional analysis.

PURPOSE: Gait speed is associated with survival in older adults and it was suggested that an elevated energy cost of walking (Cw) is an important determinant of gait speed reduction. Thus far, little is known about the factors that contribute to a lower Cw but it was shown that lower body strength training could reduce the Cw. Therefore, the objective of this study was to investigate the relationship between lower body strength and the Cw in a cohort of healthy older adults. METHODS: A total of 48 participants were included in this study (70.7 ± 5.4 years). After a geriatric and a neuropsychological assessment, participants underwent a fitness testing protocol which included a maximal oxygen uptake test, assessment of the Cw at 4 km h-1 on a treadmill, an isokinetic maximal strength test for the ankle, knee and hip joints and a body composition assessment. Relationships between strength variables and the Cw were assessed with partial correlations and linear regression analyses. RESULTS: Hip extensors and hip flexors peak torque was significantly correlated with the Cw (r = -0.36 and -0.32, respectively; p < 0.05). A tendency towards significance was identified for the ankle plantar flexors (r = -0.25, p = 0.09). Hip extensors peak torque was the only significant neuromuscular parameter included in the linear regression analysis (p < 0.05). CONCLUSION: These results show that hip extensors are an important muscle group with regards to the Cw measured on a treadmill in this cohort of healthy older adults.