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Makizako H.,Center for Gerontology and Social Science | Makizako H.,Japan Society for the Promotion of Science | Makizako H.,Mobility and Cognitive Neuroscience Laboratory | Liu-Ambrose T.,Mobility and Cognitive Neuroscience Laboratory | And 9 more authors.
Journals of Gerontology - Series A Biological Sciences and Medical Sciences | Year: 2015

Background. Greater physical activity (PA) is associated with better memory performance and greater hippocampal volume in older adults. However, most studies to date assessed PA via questionnaires and thereby lacked objective characterization of PA (eg, intensity, duration, etc.). Thus, we currently do not have a comprehensive understanding of PA characteristics that are important for neuroprotection, especially among older adults with mild cognitive impairment (MCI). Thus, using triaxial accelerometers, we examined the association between light- and moderate-intensity PA, total duration of PA, hippocampal volume, and memory in older adults with MCI. Methods. This cross-sectional study involved 310 older adults with MCI who completed neuropsychological tests of memory, and structural magnetic resonance imaging. Participants were instructed to wear the accelerometer on an elastic band on their hip at all times for 2 weeks. Average daily duration of light, moderate, and total PA (min/day) was calculated. Results. Moderate PA was associated with hippocampal volume (β =. 167, p =. 003) after controlling for age, but light PA (β = -.021, p =. 713) and total PA (β =. 011, p =. 844) were not. Both light and moderate PAs were not associated with memory performance. Structural equation modeling demonstrated that moderate PA was not directly associated with memory but significantly contributed to hippocampal volume; hippocampal volume loss was significantly and directly associated with poor memory performance. Conclusions. Our results suggest that the benefits of moderate PA on memory among older adults with MCI are mediated by hippocampal volume. Furthermore, light PA may not reduce dementia risk among older adults with MCI. © 2014 The Author. Source

Gregory M.A.,University of Western Ontario | Gregory M.A.,Lawson Health Research Institute | Gill D.P.,Lawson Health Research Institute | Gill D.P.,University of Western Ontario | And 14 more authors.
BMC Geriatrics | Year: 2016

Background: Dementia is associated with cognitive and functional deficits, and poses a significant personal, societal, and economic burden. Directing interventions towards older adults with self-reported cognitive complaints may provide the greatest impact on dementia incidence and prevalence. Risk factors for cognitive and functional deficits are multifactorial in nature; many are cardiovascular disease risk factors and are lifestyle-mediated. Evidence suggests that multiple-modality exercise programs can provide cognitive and functional benefits that extend beyond what can be achieved from cognitive, aerobic, or resistance training alone, and preliminary evidence suggests that novel mind-motor interventions (i.e., Square Stepping Exercise; SSE) can benefit cognition and functional fitness. Nevertheless, it remains unclear whether multiple-modality exercise combined with mind-motor interventions can benefit diverse cognitive and functional outcomes in older adults with cognitive complaints. Methods/Design: The Multiple-Modality, Mind-Motor (M4) study is a randomized controlled trial investigating the cognitive and functional impact of combined physical and cognitive training among community-dwelling adults with self-reported cognitive complaints who are 55 years of age or older. Participants are randomized to a Multiple-Modality and Mind-Motor (M4) intervention group or a Multiple-Modality (M2) comparison group. Participants exercise for 60 minutes/day, 3-days/week for 24 weeks and are assessed at baseline, 24 weeks and 52 weeks. The primary outcome is global cognitive function at 24 weeks, derived from the Cambridge Brain Sciences computerized cognitive battery. Secondary outcomes are: i) global cognitive function at 52 weeks; ii) domain-specific cognitive function at 24 and 52 weeks; iii) mobility (gait characteristics under single and dual-task conditions and balance); and 3) vascular health (blood pressure and carotid arterial measurements). We will analyze data based on an intent-to-treat approach, using mixed models for repeated measurements. Discussion: The design features of the M4 trial and the methods included to address previous limitations within cognitive and exercise research will be discussed. Results from the M4 trial will provide evidence of combined multiple-modality and cognitive training among older adults with self-reported cognitive complaints on cognitive, mobility-related and vascular outcomes. Trial Registration: ClinicalTrials.gov NCT02136368. © 2016 Gregory et al. Source

Gregory M.A.,University of Western Ontario | Gregory M.A.,Lawson Health Research Institute | Gill D.P.,University of Western Ontario | Gill D.P.,Lawson Health Research Institute | And 13 more authors.
Archives of Gerontology and Geriatrics | Year: 2016

Background: Gait abnormalities and vascular disease risk factors are associated with cognitive impairment in aging. Objective: To determine the impact of group-based exercise and dual-task training on gait and vascular health, in active community-dwelling older adults without dementia. Methods: Participants [n = 44, mean (SD) age: 73.5 (7.2) years, 68% female] were randomized to either intervention (exercise + dual-task; EDT) or control (exercise only; EO). Each week, for 26 weeks, both groups accumulated 50 or 75 min of aerobic exercise from group-based classes and 45 min of beginner-level square stepping exercise (SSE). Participants accumulating only 50 min of aerobic exercise were instructed to participate in an additional 25 min each week outside of class. The EDT group also answered cognitively challenging questions while performing SSE (i.e., dual-task training). The effect of the interventions on gait and vascular health was compared between groups using linear mixed effects models. Results: At 26 weeks, the EDT group demonstrated increased dual-task (DT) gait velocity [difference between groups in mean change from baseline (95% CI): 0.29 m/s (0.16-0.43), p < 0.001], DT step length [5.72 cm (2.19-9.24), p = 0.002], and carotid intima-media thickness [0.10 mm (0.003-0.20), p = 0.04], as well as reduced DT stride time variability [8.31 coefficient of variation percentage points (-12.92 to -3.70), p < 0.001], when compared to the EO group. Conclusions: Group-based exercise combined with dual-task training can improve DT gait characteristics in active older adults without dementia. © 2015 Elsevier Ireland Ltd. Source

Gill D.P.,University of Western Ontario | Gill D.P.,Lawson Health Research Institute | Gill D.P.,University of Washington | Gregory M.A.,Lawson Health Research Institute | And 10 more authors.
Medicine and Science in Sports and Exercise | Year: 2016

Background More evidence is needed to conclude that a specific program of exercise and/or cognitive training warrants prescription for the prevention of cognitive decline. We examined the effect of a group-based standard exercise program for older adults, with and without dual-task training, on cognitive function in older adults without dementia. Methods We conducted a proof-of-concept, single-blinded, 26-wk randomized controlled trial whereby participants recruited from preexisting exercise classes at the Canadian Centre for Activity and Aging in London, Ontario, were randomized to the intervention group (exercise + dual-task [EDT]) or the control group (exercise only [EO]). Each week (2 or 3 d·wk-1), both groups accumulated a minimum of 50 min of aerobic exercise (target 75 min) from standard group classes and completed 45 min of beginner-level square-stepping exercise. The EDT group was also required to answer cognitively challenging questions while doing beginner-level square-stepping exercise (i.e., dual-task training). The effect of interventions on standardized global cognitive function (GCF) scores at 26 wk was compared between the groups using the linear mixed effects model approach. Results Participants (n = 44; 68% female; mean [SD] age: 73.5 [7.2] yr) had on average, objective evidence of cognitive impairment (Montreal Cognitive Assessment scores, mean [SD]: 24.9 [1.9]) but not dementia (Mini-Mental State Examination scores, mean [SD]: 28.8 [1.2]). After 26 wk, the EDT group showed greater improvement in GCF scores compared with the EO group (difference between groups in mean change [95% CI]: 0.20 SD [0.01-0.39], P = 0.04). Conclusions A 26-wk group-based exercise program combined with dual-task training improved GCF in community-dwelling older adults without dementia. © 2015 by the American College of Sports Medicine. Source

Ten Brinke L.F.,Maastricht University | Bolandzadeh N.,UBC | Bolandzadeh N.,Djavad Mowafaghian Center for Brain Health | Nagamatsu L.S.,UBC | And 8 more authors.
British Journal of Sports Medicine | Year: 2015

Background: Mild cognitive impairment (MCI) is a well-recognised risk factor for dementia and represents a vital opportunity for intervening. Exercise is a promising strategy for combating cognitive decline by improving brain structure and function. Specifically, aerobic training (AT) improved spatial memory and hippocampal volume in healthy community-dwelling older adults. In older women with probable MCI, we previously demonstrated that resistance training (RT) and AT improved memory. In this secondary analysis, we investigated: (1) the effect of RT and AT on hippocampal volume and (2) the association between change in hippocampal volume and change in memory. Methods: 86 women aged 70-80 years with probable MCI were randomly assigned to a 6-month, twice-weekly programme of: (1) AT, (2) RT or (3) balance and tone training (BAT; ie, control). At baseline and trial completion, participants performed a 3T MRI scan to determine hippocampal volume. Verbal memory and learning were assessed by Rey's Auditory Verbal Learning Test. Results: Compared with the BAT group, AT significantly improved left, right and total hippocampal volumes ( p≤0.03). After accounting for baseline cognitive function and experimental group, increased left hippocampal volume was independently associated with reduced verbal memory and learning performance as indexed by loss after interference (r=0.42, p=0.03). Conclusions: Aerobic training signi ficantly increased hippocampal volume in older women with probable MCI. More research is needed to ascertain the relevance of exercise-induced changes in hippocampal volume on memory performance in older adults with MCI. Trail registration number NCT00958867. © 2015, BMJ Publishing Group. All rights reserved. Source

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