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1.
The effects of physical activity on cognition in older adults have been extensively investigated in the last decade. Different interventions such as aerobic, strength, and gross motor training programs have resulted in improvements in cognitive functions. However, the mechanisms underlying the relationship between physical activity and cognition are still poorly understood. Recently, it was shown that acute bouts of exercise resulted in reduced executive control at higher relative exercise intensities. Considering that aging is characterized by a reduction in potential energy (V·O2 max − energy cost of walking), which leads to higher relative walking intensity for the same absolute speed, it could be argued that any intervention aimed at reducing the relative intensity of the locomotive task would improve executive control while walking. The objective of the present study was to determine the effects of a short-term (8 weeks) high-intensity strength and aerobic training program on executive functions (single and dual task) in a cohort of healthy older adults. Fifty-one participants were included and 47 (age, 70.7 ± 5.6) completed the study which compared the effects of three interventions: lower body strength + aerobic training (LBS-A), upper body strength + aerobic training (UBS-A), and gross motor activities (GMA). Training sessions were held 3 times every week. Both physical fitness (aerobic, neuromuscular, and body composition) and cognitive functions (RNG) during a dual task were assessed before and after the intervention. Even though the LBS-A and UBS-A interventions increased potential energy to a higher level (Effect size: LBS-A—moderate, UBS-A—small, GMA—trivial), all groups showed equivalent improvement in cognitive function, with inhibition being more sensitive to the intervention. These findings suggest that different exercise programs targeting physical fitness and/or gross motor skills may lead to equivalent improvement in cognition in healthy older adults. Such results call for further investigation of the multiple physiological pathways by which physical exercise can impact cognition in older adults.  相似文献   

2.
Dual tasks that involve walking and cognitive interference tests are commonly used in mobility assessments and interventions. However, factors that explain variance in dual-task performance costs are poorly understood. We, therefore, examined the moderating effects of two putative constructs, postural reserve and hazard estimate, on performance on a walking while talking paradigm. Participants were 285 non-demented older adults (mean age = 76.9 years; %female = 54.4). Postural reserve was operationalized as the presence or absence of clinical gait abnormalities. An empirical factor, based on measures of executive functions, served as a marker for hazard estimate. The moderation effects of postural reserve and hazard estimate on dual-task costs were examined via two-way interactions in a joint linear mixed effect model. Significant dual-task costs were observed for gait speed (95% CI = 30.814 to 39.121) and cognitive accuracy (95% CI = 6.568 to 13.607). High hazard estimate had a protective effect against decline in gait speed (95% CI = −8.372 to −0.151) and cognitive accuracy (95% CI = −8.372 to −0.680). Poor postural reserve was associated with reduced decline in gait speed (95% CI = −9.611 to −0.702) but did not moderate the decline in cognitive accuracy (95% CI = −3.016 to 4.559). Assessing postural reserve and hazard estimate can help improve mobility risk assessment procedures and interventions for individuals with cognitive and movement disorders.  相似文献   

3.
Offspring of parents with exceptional longevity (OPEL), who are more likely to carry longevity-associated genotypes, may age more successfully than offspring of parents with usual survival (OPUS). Maintenance of physical function is a key attribute of successful aging. While many genetic and non-genetic factors interact to determine physical phenotype in aging, examination of the contribution of exceptional parental longevity to physical function in aging is limited. The LonGenity study recruited a relatively genetically homogenous cohort of Ashkenazi Jewish (AJ) adults age 65 and older, who were defined as either OPEL (having at least one parent who lived to age 95 or older) or OPUS (neither parent survived to age 95). Subjective and objective measures of physical function were compared between the two groups, accounting for potential confounders. Of the 893 LonGenity subjects, 365 were OPEL and 528 were OPUS. OPEL had better objective and subjective measures of physical function than OPUS, especially on unipedal stance (p = 0.009) and gait speed (p = 0.002). Results support the protective role of exceptional parental longevity in preventing decline in physical function, possibly via genetic mechanisms that should be further explored.  相似文献   

4.
With aging, customary gait patterns change and energetic efficiency declines, but the relationship between these alterations is not well understood. If gait characteristics that develop with aging explain part of the decline in energetic efficiency that occur in most aging individuals, then efforts to modify these characteristics could delay or prevent mobility limitation. This study characterizes gait patterns in older persons with and without knee pain and tests the hypothesis that changes in gait characteristics due to knee pain are associated with increased energetic cost of walking in older adults. Study participants were 364 men and 170 women aged 60 to 96 years enrolled in the Baltimore Longitudinal Study of Aging (BLSA), of whom 86 had prevalent knee pain. Gait patterns were assessed at participant self-selected usual pace in the gait laboratory, and the energetic cost of walking was assessed by indirect calorimetry during self-selected usual pace walking over 2.5 min in a tiled corridor using a portable equipment. Participants with knee pain were less energetically efficient than those without pain (oxygen consumption 0.97 vs. 0.88 ml/(10 m · 100 kg); p = 0.002) and had slower gait speed and smaller range of motion (ROM) at the hip and knee joints (p < 0.05, for all). Slower gait speed and lower knee ROM in participants with knee pain and longer double support time and higher ankle ROM in participants without knee pain were associated with lower energetic efficiency (p < 0.05, for all). Slower gait speed and lower knee ROM were correlates of knee pain and were found to mediate the association between age and oxygen consumption. Although knee pain is associated with a higher energetic cost of walking, gait characteristics associated with energetic efficiency differ by pain status which suggests that compensatory strategies both in the presence and absence of pain may impact gait efficiency.  相似文献   

5.
Mild parkinsonian signs (MPS) and gait abnormalities are common in aging, but the association between MPS and objective gait measures is not established in the elderly. This study aims to identify the link between MPS and quantitative gait measures, as well as to determine the pathogenesis of MPS in non-demented community-dwelling older adults without idiopathic Parkinson’s disease or other parkinsonian syndromes. Three hundred seventy-four non-demented older adults (mean age, 76.44 ± 6.71 years, 57 % women) participated in this study, where comprehensive neurological and medical assessments were conducted. We defined MPS based on the presence of any one of bradykinesia, rigidity, or rest tremor. Velocity and spatial, temporal, and variability gait parameters were recorded using an instrumented walkway. The associations of MPS and gait parameters as well as the relationship of individual MPS with medical illnesses were assessed with linear regressions controlling for key covariates. Participants with MPS walked slower and with disturbed spatial and variability components of gait compared to those without MPS. Bradykinesia was associated with worse spatial and variability gait parameters. This association was only significant for axial bradykinesia, but not for the presence of bradykinesia in the limbs. Cerebrovascular disease (β = .20, p < .01) was associated with bradykinesia, whereas cardiovascular disease (β = .15, p < .05) was associated with rigidity. Among MPS, bradykinesia but not rigidity or tremor was associated with worse quantitative gait performance in older adults. Cerebrovascular disease, a preventable condition, was specifically associated with bradykinesia.  相似文献   

6.
Aim: To examine gender differences in regards to the disagreement between walking speed and self‐reported mobility limitations, and, furthermore, to explore the items that affect each physical function task by comparing slow walking speed and self‐reported mobility limitation in community‐dwelling older adults. Methods: The subjects consisted of 1381 community‐dwelling men and women aged 65–84 years who were classified into four categories according to a combination of mobility status measured by a slow walking speed (usual gait speed < 1.0 m/s) and self‐reported mobility limitation (difficulty walking 1 km). The physical function tests comprised one‐legged stance, tandem stance, functional reach, tandem walk, alternate step and five chair sit‐to‐stand. Results: The prevalence of limitations increased more rapidly with age in women than in men for five mobility tasks (P < 0.001). The percent difference between slow walking speed and self‐reported mobility limitation was higher in women (24%) than men (19%). The multivariate logistic regression model showed that after adjusting for all covariates, the tandem walk, alternate step and five chair sit‐to‐stand were identified as effective physical function tests in regards to mobility status as measured by the difference between slow walking speed and self‐reported mobility limitation (P < 0.01). Conclusion: Tandem walk, alternate step and five chair sit‐to‐stand are important effective items of physical function and permit good comparisons between slow walking speed and self‐reported mobility limitation in community‐dwelling older adults. Geriatr Gerontol Int 2012; 12: 50–58.  相似文献   

7.
Relative and absolute muscle mass and muscle strength are used as diagnostic criteria for sarcopenia. We aimed to assess which diagnostic criteria are most associated with physical performance in 180 young (18–30 years) and 281 healthy old participants (69–81 years) of the European study MYOAGE. Diagnostic criteria included relative muscle mass (total or appendicular lean mass (ALM) as percentage of body mass), absolute muscle mass (ALM/height squared and total lean mass), knee extension torque, and handgrip strength. Physical performance comprised walking speed, Timed Up and Go test (TUG), and in a subgroup physical fitness. Diagnostic criteria for sarcopenia and physical performance were standardized, and the associations were analyzed using linear regression models stratified by age category, with adjustments for age, gender, and country. In old participants, relative muscle mass was associated with faster walking speed, faster TUG, and higher physical fitness (all p < 0.001). Absolute muscle mass was not associated with physical performance. Knee extension torque and handgrip strength were associated with faster walking speed (both p ≤ 0.003). Knee extension torque was associated with TUG (p = 0.001). Knee extension torque and handgrip strength were not associated with physical fitness. In young participants, there were no significant associations between diagnostic criteria for sarcopenia and physical performance, except for a positive association between relative muscle mass and physical fitness (p < 0.001). Relative muscle mass, defined as lean mass or ALM percentage, was most associated with physical performance. Absolute muscle mass including ALM/height squared was not associated with physical performance. This should be accounted for when defining sarcopenia.  相似文献   

8.
Walking speed is a key vital sign in older people. Given the implications of slower gait speed, a large literature has identified health-related, behavioral, cognitive, and biological factors that moderate age-related decline in mobility. The present study aims to contribute to existing knowledge by examining whether subjective age, how old or young individuals experience themselves to be relative to their chronological age, contributes to walking speed. Participants were drawn from the 2008 and 2012 waves of the Health and Retirement Study (HRS, N = 2970) and the 2011 and 2013 waves of the National Health and Aging Trends Study (NHATS, N = 5423). In both the HRS and the NHATS, linear regression analysis revealed that a younger subjective age was associated with faster walking speed at baseline and with less decline over time, controlling for age, sex, education, and race. These associations were partly accounted for by depressive symptoms, disease burden, physical activity, cognition, body mass index, and smoking. Additional analysis revealed that feeling younger than one’s age was associated with a reduced risk of walking slower than the frailty-related threshold of 0.6 m/s at follow-up in the HRS. The present study provides novel and consistent evidence across two large prospective studies for an association between the subjective experience of age and walking speed of older adults. Subjective age may help identify individuals at risk for mobility limitations in old age and may be a target for interventions designed to mitigate functional decline.  相似文献   

9.
Aging is associated with a progressive decline in skeletal muscle mass. It has been hypothesized that an attenuated muscle protein synthetic response to the main anabolic stimuli may contribute to the age-related loss of muscle tissue. The aim of the present study was to compare the muscle protein synthetic response following ingestion of a meal-like amount of dietary protein plus carbohydrate between healthy young and older men. Twelve young (21 ± 1 years) and 12 older (75 ± 1 years) men consumed 20 g of intrinsically l-[1-13C]phenylalanine-labeled protein with 40 g of carbohydrate. Ingestion of specifically produced intrinsically l-[1-13C]phenylalanine-labeled protein allowed us to assess the subsequent incorporation of casein-derived amino acids into muscle protein. Blood samples were collected at regular intervals, with muscle biopsies obtained prior to and 2 and 6 h after protein plus carbohydrate ingestion. The acute post-prandial rise in plasma glucose and insulin concentrations was significantly greater in the older compared with the younger males. Plasma amino acid concentrations increased rapidly following drink ingestion in both groups. However, plasma leucine concentrations were significantly lower at t = 90 min in the older when compared with the young group (P < 0.05). Muscle protein-bound l-[1-13C]phenylalanine enrichments increased to 0.0071 ± 0.0016 and 0.0072 ± 0.0013 mole percent excess (MPE) at 2 h and 0.0229 ± 0.0016 and 0.0213 ± 0.0024 MPE at 6 h following ingestion of the intrinsically labeled protein in the young and older males, respectively, with no differences between groups (P > 0.05). We conclude that the use of dietary protein-derived amino acids for muscle protein synthesis is not impaired in healthy older men following intake of protein plus carbohydrate.  相似文献   

10.
A single bout of acute exercise increases oxidative stress and stimulates a transient increase in antioxidant enzymes. We asked whether this response would induce protection from a subsequent oxidative challenge, different from that of exercise, and whether the effects were affected by aging. We compared young (20 ± 1 years, n = 8) and older (58 ± 6 years, n = 9) healthy men and women. Resistance to oxidative stress was measured by the F2-isoprostane response to forearm ischemia/reperfusion (I/R) trial. Each participant underwent the I/R trial twice, in random order; once after performing 45 min of cycling on the preceding day (IRX) and a control trial without any physical activity (IRC). Baseline F2-isoprostane levels were significantly lower at IRX compared to IRC (P < 0.05) and not different between groups. F2-isoprostane response to IRX was significantly lower compared to IRC in young (P < 0.05) but not different in the older group. Superoxide dismutase activity in response to acute exercise was significantly higher in young compared to older adults (P < 0.05). These data suggest that signal transduction of acute exercise may be impaired with aging. Repeated bouts of transient reactive oxygen species production as seen with regular exercise may be needed to increase resistance to oxidative stress in older individuals.  相似文献   

11.
Walking speed and muscular strength are two main markers of health in adulthood. Previous studies have shown that personality traits may predict these two outcomes. However, little is known about the mechanisms underlying these relationships. Thus, the present study examined whether personality traits are associated with walking speed and muscular strength through the mediating role of subjective age (how young or old individuals experience themselves to be), attitudes toward aging and physical self-perceptions.Community-dwelling older women (N = 243; Mage = 73.0; SDage = 6.5) were recruited. For reasons of recruitment feasibility, participants were only older women. They were requested to complete a questionnaire measuring personality, subjective age, attitudes toward aging and physical self-perceptions. Following this, their walking speed and their muscular strength were investigated. Data were analyzed using structural equation modeling. In line with the literature, we extended the associations between extraversion, neuroticism, conscientiousness and walking speed and between conscientiousness, neuroticism, openness and muscular strength. Physical self-perceptions appear to be a robust mediator between personality traits and walking speed whereas attitudes toward aging and subjective age mediated the personality traits/muscular strength relationship.This study provides evidence, for the first time, that the associations between personality traits and physical capacities are different according to the physical capacities investigated. Based on these results, it could be interesting to adapt physical activity interventions to the psychological profile of older adults.  相似文献   

12.
13.
Training that focuses on strength, balance, and endurance, the so-called combined exercise, can enhance physical function, including gait, according to a literature review. However, the effects of combined exercise on improving gait variability are limited. The objective of this study is to investigate the effects of 12 weeks of combined exercise comprised of resistance, endurance, and balance training on gait performance in older adults. Twenty-nine community-dwelling older adults were recruited and assigned to either the experimental group (n = 17) or the control group (n = 12). The 12-week intervention was a combined exercise program at 1 h per day and 3 days per week. The participants received an assessment for both a 6-min walk and gait during both habitual walking and fast walking conditions at pre-intervention and after 8 and 12 weeks of exercise. The 6-min walk was used to assess gait endurance. GAITRite was used to evaluate gait. An analysis of covariance with the pretest score as the covariate was used to determine the difference in each dependent variable between groups. The level of significance was set as p less than 0.05. Our results showed significant between-group effects in the 6-min walk and velocity, stride time, and stride length in both conditions after 8 weeks of exercise and significant between-group effects in the 6-min walk test and all selected gait parameters in both conditions after 12 weeks of exercise. Our findings demonstrate that a 12-week combined exercise program may positively affect gait endurance and gait performance including gait variability in habitual walking and fast walking conditions among older adults. The current study provides important evidence of short-term combined exercise effects on improvements in gait performance.  相似文献   

14.
Sarcopenia is thought to play a major role in the functional impairment that occurs with old age. In clinical practice, sarcopenia is often determined by measuring handgrip strength. Here, we compared the lower limb quadriceps strength to the handgrip strength in their association with health outcomes in older adults in primary care. Our study population consisted of older adults (n = 764, 68.2 % women, median age 83) that participated in the Integrated Systemic Care for Older People (ISCOPE) study. Participants were visited at baseline to measure quadriceps strength and handgrip strength. Data on health outcomes were obtained at baseline and after 12 months (including life satisfaction, disability in daily living, GP contact-time and hospitalization). Quadriceps strength and handgrip strength showed a weak association (β = 0.42 [95 % CI 0.33–0.50]; R2 = 0.17). Quadriceps strength and handgrip strength were independently associated with health outcomes at baseline, including quality of life, disability in daily living, GP contact-time, hospitalization, and gait speed. Combined weakness of the quadriceps and handgrip distinguished a most vulnerable subpopulation that presented with the poorest health outcomes. At follow-up, handgrip strength showed an association with quality of life (β = 0.05; P = 0.002) and disability in daily living (β = −0.5; P = 0.004). Quadriceps weakness did not further contribute to the prediction of the measured health outcomes. We conclude that quadriceps strength is only moderately associated with handgrip strength in an older population and that the combination of quadriceps strength and handgrip strength measurements may aid in the identification of older adults in primary care with the poorest health outcomes. In the prediction of poor health outcomes, quadriceps strength measurements do not show an added value to the handgrip strength.  相似文献   

15.
16.
A U-shaped relationship between cognitive demand and gait control may exist in dual-task situations, reflecting opposing effects of external focus of attention and attentional resource competition. The purpose of the study was twofold: to examine whether gait control, as evaluated from step-to-step variability, is related to cognitive task difficulty in a U-shaped manner and to determine whether age modifies this relationship. Young and older adults walked on a treadmill without attentional requirement and while performing a dichotic listening task under three attention conditions: non-forced (NF), forced-right (FR), and forced-left (FL). The conditions increased in their attentional demand and requirement for inhibitory control. Gait control was evaluated by the variability of step parameters related to balance control (step width) and rhythmic stepping pattern (step length and step time). A U-shaped relationship was found for step width variability in both young and older adults and for step time variability in older adults only. Cognitive performance during dual tasking was maintained in both young and older adults. The U-shaped relationship, which presumably results from a trade-off between an external focus of attention and competition for attentional resources, implies that higher-level cognitive processes are involved in walking in young and older adults. Specifically, while these processes are initially involved only in the control of (lateral) balance during gait, they become necessary for the control of (fore-aft) rhythmic stepping pattern in older adults, suggesting that attentional resources turn out to be needed in all facets of walking with aging. Finally, despite the cognitive resources required by walking, both young and older adults spontaneously adopted a “posture second” strategy, prioritizing the cognitive task over the gait task.  相似文献   

17.
OBJECTIVE: To test the hypothesis that age-associated changes in physical function, particularly walking performance, are influenced by ageism and that the activation of positive sterotypes of aging can partially reverse these changes. DESIGN: Randomized intervention study. SETTING: General community. PARTICIPANTS: Forty-seven community-dwelling men and women (63-82 years old) who walked independently and described themselves as healthy. INTERVENTION: Thirty-minute exposure to the subconscious reinforcement of either a positive or negative stereotype of aging while subjects played a computer game. MEASUREMENTS: Pre- and postintervention measures of gait speed and percent swing time (the time spent with one foot in the air during walking). Health and psychosocial status were also evaluated. RESULTS: Significant increases in walking speed (9%+/-2%; P < .001) and percent swing time (percent change: 1.1%+/-0.4%; P = .023) were observed in subjects who received reinforcement of positive stereotypes of aging. Gait speed and swing time did not change in those who received reinforcement of negative stereotypes of aging. The observed improvements in gait were related to the positive intervention, but were not related to age, gender, health status, or psychosocial status. CONCLUSIONS: Stereotypes of aging apparently have a powerful impact on the gait of older persons. Interventions designed to enhance perceptions of old age may prove beneficial in helping to improve gait and functional independence among older persons. In the future, positive changes in society's view of aging may also help to reduce and prevent age-related declines in function and the associated deleterious consequences.  相似文献   

18.
BACKGROUND AND AIMS: Gait changes in dual-task conditions have been associated with an increased risk of falling in older adults, and become more important in increasingly frail older adults. We studied the relationship between commonly known intrinsic risk factors for falls and dual-task related gait changes among transitional frail older adults. METHODS: Walking time and number of steps were measured while walking alone and while walking with counting backward on a 10-m walkway in 66 transitional frail older adults (mean age 83.6+/-6.1, 84.9% women). Uni- and multiple linear regression analyses were performed to explore the relationship between dual-task related gait changes (walking time and number of steps) and age over 85 years, polymedication, psychoactive drugs, poor distance vision, abnormal mobility and cognitive impairment. RESULTS: Compared with walking alone, both walking time and number of steps increased significantly while counting backward (p<0.001). Polymedication and abnormal mobility were associated with a significant increase of walking time and number of steps (p<0.01 for unadjusted change, p<0.05 for adjusted change). CONCLUSIONS: Dual-task related gait changes were closely correlated with polymedication and impaired mobility in our sample of transitional frail older adults. These findings give some insight into the complexity of performing attention-demanding tasks while walking and accentuate the need for multi-factorial, personalized intervention strategies, to prevent decline in dual-task performance in this fall-prone population.  相似文献   

19.
Background/Study Context: The safety of older pedestrians in road crossing has received considerable attention but previous studies measure gait characteristics only under unloaded conditions. The aim of this study was to investigate the start-up time and walking speed under loaded conditions that reflect daily activities of older adults in Singapore.

Methods: Thirty-two older adults (age (SD) = 69.4 (7.0) years) and 20 young controls (age (SD) = 23.1 (2.0) years) walked under four conditions: (1) unloaded, (2) pushing a stroller loaded with 10 kg, (3) pulling a shopping cart loaded with 15 kg, and (4) carrying two shopping bags each loaded with 2 kg. Start-up time was determined from video recordings and walking speed measured using timing gates. A mixed-model analysis of variance (ANOVA; age by walking condition) with repeated measures was applied.

Results: Start-up times were slower in the stroller and shopping cart conditions compared with the unloaded and shopping bags conditions. Loading reduced walking speed, with the shopping cart being the slowest, followed by the stroller and then the shopping bags. A significant interaction was found, with young controls reducing their speeds more substantially while handling the stroller/cart than older participants.

Conclusion: Loading caused a compromise in start-up time and walking speed. The start-up time was slower when pushing a stroller or pulling a shopping cart but remained unaffected by carrying shopping bags. Speed was reduced under all loaded conditions, with a greater effect in young than older participants when handling a stroller or shopping cart.  相似文献   

20.

Background

Approximately 40% of hospitalized older adults have cognitive impairment (CI) and are more prone to hospital-acquired complications. The Institute of Medicine suggests using health information technology to improve the overall safety and quality of the health care system.

Objective

Evaluate the efficacy of a clinical decision support system (CDSS) to improve the quality of care for hospitalized older adults with CI.

Design

A randomized controlled clinical trial.

Setting

A public hospital in Indianapolis.

Population

A total of 998 hospitalized older adults were screened for CI, and 424 patients (225 intervention, 199 control) with CI were enrolled in the trial with a mean age of 74.8, 59% African Americans, and 68% female.

Intervention

A CDSS alerts the physicians of the presence of CI, recommends early referral into a geriatric consult, and suggests discontinuation of the use of Foley catheterization, physical restraints, and anticholinergic drugs.

Measurements

Orders of a geriatric consult and discontinuation orders of Foley catheterization, physical restraints, or anticholinergic drugs.

Results

Using intent-to-treat analyses, there were no differences between the intervention and the control groups in geriatric consult orders (56% vs 49%, P = 0.21); discontinuation orders for Foley catheterization (61.7% vs 64.6%, P = 0.86); physical restraints (4.8% vs 0%, P = 0.86), or anticholinergic drugs (48.9% vs 31.2%, P = 0.11).

Conclusion

A simple screening program for CI followed by a CDSS did not change physician prescribing behaviors or improve the process of care for hospitalized older adults with CI.

Electronic supplementary material

The online version of this article (doi:10.1007/s11606-012-1994-8) contains supplementary material, which is available to authorized users.KEY WORDS: cognitive impairment, clinical trial, decision support, hospitalized elders  相似文献   

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