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1.
Joint proprioception plays an important role in the generation of coordinated movements, maintenance of normal body posture, body conditioning, motor learning, and relearning. Previous studies have demonstrated that proprioceptive function of the elderly can be enhanced via specific exercises; however, not all of the elderly can actively and safely participate in physical activities. The purpose of this study was to evaluate the effects of rapid repetitive passive movement in an average velocity of 90°/s on knee proprioception in the elderly. A repeated-measure design was employed. Two age groups (12 young/12 elderly) were intervened with repetitive passive movements of 60 repetitions to the knee joint via two machines (isokinetic dynamometer/self-designed machine) in separate days. Changes in proprioception were evaluated via joint active repositioning and kinesthesia, both before and after the intervention. The results revealed that all subjects demonstrated good test–retest reliabilities on proprioceptive measurements. For the active repositioning and kinesthesia, significant statistical main effects were found for group and time, but not for machine. No statistical interactions were revealed. Despite of age-related proprioceptive declines, elderly subjects could benefit from rapid repetitive passive movements. This indicates that repetitive passive movement may be an alternative to physical activity for those who are home-bound, in a sedentary lifestyle, or with other health conditions that may limit their abilities to actively maintain or strengthen joint proprioception.  相似文献   

2.
《The aging male》2013,16(2):91-95
Elderly subjects have a lower energy requirement compared to young adults as a result of lower physical activity and a lower basal metabolic rate. A lower energy intake in the elderly could lead to undesirable low intakes of essential nutrients. The reduction of the energy turnover is caused by, or a consequence of, a decrease in active cell mass. Thus, the effect of exercise training on habitual activity across age ranges, and age-related changes in body composition in relation to habitual activity level, are investigated here. The focus is on data on physical activity and body composition obtained with doubly labelled water. The results suggest that exercise training does not affect energy requirement in the elderly and the age-related decrease in fat-free mass is not delayed in subjects with a relatively high habitual activity level. Beneficial effects of exercise training in the elderly are endurance, flexibility, range of motion and balance control, all contributing to a delay in the age-induced impairment of personal mobility. Energy intake will inevitably go down as a result of a reduction of the energy requirement. Thus, the nutrition of elderly subjects needs more attention with regard to the essential nutrients than the nutrition of younger adults.  相似文献   

3.
With increasing age, it appears that masters athletes competing in anaerobic events (10–100 s) decline linearly in performance until 70 years of age, after which the rate of decline appears to accelerate. This decline in performance appears strongly related to a decreased anaerobic work capacity, which has been observed in both sedentary and well-trained older individuals. Previously, a number of factors have been suggested to influence anaerobic work capacity including gender, muscle mass, muscle fiber type, muscle fiber size, muscle architecture and strength, substrate availability, efficiency of metabolic pathways, accumulation of reaction products, aerobic energy contribution, heredity, and physical training. The effects of sedentary aging on these factors have been widely discussed within literature. Less data are available on the changes in these factors in masters athletes who have continued to train at high intensities with the aim of participating in competition. The available research has reported that these masters athletes still demonstrate age-related changes in these factors. Specifically, it appears that morphological (decreased muscle mass, type II muscle fiber atrophy), muscle contractile property (decreased rate of force development), and biochemical changes (changes in enzyme activity, decreased lactate production) may explain the decreased anaerobic performance in masters athletes. However, the reduction in anaerobic work capacity and subsequent performance may largely be the result of physiological changes that are an inevitable result of the aging process, although their effects may be minimized by continuing specific high-intensity resistance or sprint training.  相似文献   

4.
Using two waves of the National Survey of Midlife Development in the United States, I compare changes in personal growth over a 10 year period among cancer survivors and individuals without cancer. Moreover, I examine joint effects of age and cohort on personal growth after a cancer diagnosis. The theoretical framework of this study integrates impairment, resilience, and thriving perspectives. Findings reveal that, although personal growth declines with age for all individuals regardless of cohort and cancer status, cancer slows the decline in personal growth with age in 1940s, 1950s, and 1960s birth cohorts, yet accelerates the age-related decline in the 1920s cohort. I argue that a sociological perspective can enhance our understanding of the interplay of developmental and sociocultural influences on psychological adjustment to cancer. Seemingly idiosyncratic psychological reactions to cancer partly reflect macrolevel processes represented by cohort differences.  相似文献   

5.
Ubiquitinated proteinaceous inclusions are the hallmark of many neurodegenerative diseases. Inefficient proteolysis might lead to the accumulation and ultimate deposition of potentially toxic entities as inclusions within neurons or glial cells. This hypothesis is supported by genetic evidence both from patient populations and from engineered mutations in genes that encode ubiquitin/proteasome components in mice. The appearance of similar inclusions in the brains of elderly individuals of normal and subclinical conditions begs the question of whether there is a general age-related decline in the ability of the ubiquitin/proteasome pathway (UPP) to recognize and eliminate abnormal proteins, and whether such a decline would be reflected by changes in the abundance or activity of some or all components of the UPP. Here we describe alterations in the aging mammalian brain that correlate with a decline in the function of the UPP and review the evidence for age-related changes in specific UPP components. These alterations are discussed within the context of prevalent theories of aging.  相似文献   

6.
A Theory of Time Preference   总被引:2,自引:0,他引:2  
This article proposes that people generally prefer present consumption to future consumption because their expected utility from consumption (eventually) falls as their mental and physical abilities (eventually) decline with age. Moreover, contrary to the ubiquitous intertemporal formulation with a constant rate of time preference and contrary to three recent theories of time preference that predict decreasing discounting as people age, this article asserts that discounting increases over the life cycle. This hypothesis is supported by data from the Panel Study of Income Dynamics as well as evidence from numerous previous studies.  相似文献   

7.
Elite master athletes with long-term devotion to physical training offer an economical means of investigating the effects of ageing and habitual exercise on maximal physical performance. Ideally, individuals with optimised living habits throughout their lives could serve as a human model of ‘primary’ or ‘inherent’ ageing, where age-related changes are not confounded by sedentary life-style and associated chronic diseases. A limitation of this approach is the selection bias as those with inherently high physical capacity and good health participate in competitive sports. The age-related decrements remain obvious, but the record performances of master athletes competing in running and jumping events are preserved at an extraordinary high level until old age. Similarly, underlying capacities such as muscle strength, power and endurance remain far above the age norms, thus providing superior functional reserves for activities of daily living. Nevertheless, even the best records may overestimate the age decrements. It is obvious that the older champions have never trained and performed as well as the current younger athletes, and that the performance of individual athletes retaining or increasing their training volume and intensity show smaller decrements over the years. The plasticity of individual development is preserved in later life thus making it possible, at least for some time, to modify the age-associated decline in the different aspects of maximal physical performance.  相似文献   

8.
Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) age-related withdrawal is very likely to be involved in the aging process and the onset of age-related diseases, giving rise to the question of whether preventing or compensating the decline of these steroids may have endocrine and clinical benefits. The aim of the present trial was to evaluate the endocrine, neuroendocrine and clinical consequences of a long-term (1 year), low-dose (25?mg/day) replacement therapy in a group of aging men who presented the clinical characteristics of partial androgen deficiency (PADAM). Circulating DHEA, DHEAS, androstenedione, total testosterone and free testosterone, dihydrotestosterone (DHT), progesterone, 17-hydroxyprogesterone, allopregnanolone, estrone, estradiol, sex hormone binding globulin (SHBG), cortisol, follicle stimulating hormone (FSH), luteinizing hormone (LH), growth hormone (GH) and insulin-like growth factor 1 (IGF-1) levels were evaluated monthly to assess the endocrine effects of the therapy, while β-endorphin values were used as a marker of the neuroendocrine effects. A Kupperman questionnaire was performed to evaluate the subjective symptoms before and after treatment.

The results showed a great modification of the endocrine profile; with the exception of cortisol levels, which remained unchanged, DHEA, DHEAS, androstenedione, total and free testosterone, DHT, progesterone, 17-hydroxyprogesterone, estrone, estradiol, GH, IGF-1 and β-endorphin levels increased significantly with respect to baseline values, while FSH, LH and SHBG levels showed a significant decrease. The Kupperman score indicated a progressive improvement in mood, fatigue and joint pain.

In conclusion, the present study demonstrates that 25?mg/day of DHEA is able to cause significant changes in the hormonal profile and clinical symptoms and can counteract the age-related decline of endocrine and neuroendocrine functions. Restoring DHEA levels to young adult values seems to benefit the age-related decline in physiological functions but, however promising, placebo-controlled trials are required to confirm these preliminary results.  相似文献   

9.
One third of adults over 65 yr old fall each year. Wide-ranging consequences include fracture, reduced activity, and death. Research synthesis suggests that falls-prevention programs can be effective in reducing falls by about 20%. Strength and balance training is the most efficacious component, and the assumed method of effect is an improvement in these performance domains. There is some evidence for this, but the authors have previously proposed an alternative method, activity restriction, leading to a reduction in subsequent falls through a reduction in exposure. The aim of this study was to examine physical activity in older fallers, applying a theory of adaptation, to ascertain predictors of habitual physical activity. Referrals to hospital- and community-based exercise programs were assessed for (a) habitual walking steps and (b) coping strategies, falls self-efficacy, social support, and balance mobility. There was no average group change in physical activity. There was high interindividual variability. Two coping strategies, loss-based selection and optimization, best explained the change in physical activity between baseline and follow-up. Notwithstanding some limitations, this work suggests further use of adaptation theory in falls research. A potential application is the creation of a profiling tool to enable clinicians to better match treatment to patient.  相似文献   

10.
Neuroimaging studies suggest that when the brain ages, more areas are involved to perform a task in order to obtain the same results. This, together with the increase in crystalized intelligence and wisdom, is usually considered as a compensatory strategy. Research has demonstrated that physical activity might also act as a strategy and be one of the main factors that can slow down age-related perceptual and cognitive decline. Research also suggests that different types of physical exercise and sport lead to different changes in perceptual and cognitive skills as well as in several areas of the brain, especially those involving multiple domains, such as exergaming, dance or some sports. This review summarizes the findings of recent studies with older adults investigating the brain and cognitive benefits of different forms of physical exercise. Visuospatial attention, which plays a critical role in our daily lives, especially for older adults, is a central part of this analysis.  相似文献   

11.
Sexual expression in later life: a review and synthesis   总被引:1,自引:0,他引:1  
In the past decade, researchers have begun to study the sexual functioning of typical older persons. This review summarizes literature on the sexuality of men and women over age 50 as researched by social and health scientists. Research on the relationship of biological factors (changes accompanying aging), health (physical, mental, and medication use), psychological factors (attitudes, information about sex), relationship factors (status, satisfaction), and sexual functioning (desire, dysfunctions, treatment) to sexual behavior is reviewed. The review suggests that (a) men and women remain sexually active into their 70s and 80s, (b) aging-related physical changes do not necessarily lead to decline in sexual functioning, and (c) good physical and mental health, positive attitudes toward sex in later life, and access to a healthy partner are associated with continued sexual activity. In turn, regular sexual expression is associated with good physical and mental health. Progress in understanding later life sexuality requires development of comprehensive theoretical models, a broad focus on intimacy, attention to measures and samples, and research on couples. Progress in understanding is especially important, given the aging of populations.  相似文献   

12.
Students (n = 257) were evaluated for scope and commitment to physical activity by use of self-reported data that assessed amount of activity per week and the obligatory or pathological nature of their activity patterns. Exhibiting atypical activity patterns, 21.8% of the students in the sample exercised 360 or more minutes per week and demonstrated at least one exercise "dependent" response pattern to queries about obligatory or pathological exercise. Although clinicians and educators should promote the many advantages of regular participation in physical activity, they should acknowledge that, for some, it may have undesirable consequences that occur at a frequency parallel to other age-related negative behaviors.  相似文献   

13.
The relationship between the gonadal steroids, testosterone and estrogen, and individual and group differences in performance on some cognitive tasks remains unclear but sex differences favoring males on some tests of visuo-spatial ability are large and robust. This aim of this review is to assess evidence for both organizational and activational effects of gonadal steroids as the principle cause of sex difference in visuo-spatial ability. Additionally, the implications of this relationship are discussed in the context of decreasing levels of gonadal steroids in aging males and psychological theories of generalized age-related cognitive decline. Based upon human and non-human research gonadal steroids have organizational effects on visuo-spatial ability in adulthood. Activational effects of gonadal steroids on visuo-spatial ability appear most dominant in older men and are necessary for maintaining optimal visuo-spatial ability; randomized clinical trials show that testosterone supplementation improves performance. Additionally, decreasing gonadal steroid levels in aging males may contribute to generalized age-related cognitive decline. Future supplementation studies in men should attempt to control for constituent abilities related to visuo-spatial task performance, and investigate interactions between dosage levels and baseline gonadal status. Further future animal research is required to investigate changes in gonadal steroid levels and their relationship to neurotransmitter systems, neural plasticity, and behavioral correlates.  相似文献   

14.
《The aging male》2013,16(4):234-243
Growth hormone (GH) secretagogues are synthetic peptidyl and non-peptidyl molecules which possess a strong, dose-dependent and reproducible GH-releasing effect after intravenous and even oral administration in humans. This effect is probably mediated via the activation of specific receptors, mainly present at the pituitary and hypothalamic level; a human pituitary GH secretogogue receptor has already been cloned, pointing to the existence of an endogenous GH secretagogue-like ligand. The GH-releasing effect of GH secretagogues is gender-independent but undergoes marked age-related variations. In fact, the effect is low at birth, increases markedly at puberty, persists at a similar level in adulthood and decreases thereafter, being already similar in middle age to that in elderly subjects. It is likely that the reduced activity of GH secretagogues in aging reflects the age-related changes in the neural control of somatotrope function. These could include the hypothetical impairment in the activity of the putative natural GH secretagogue-like ligand. Prolonged treatment with non-peptidyl GH secretagogues has been shown to restore spontaneous GH pulsatility and insulin-like growth factor I (IGF-I) levels in aged humans as well as in animals. The possibility that chronic treatment with GH secretagogues in aging rejuvenates the activity of the GH/IGF-I axis and counteracts the age-related changes in body composition, structure functions and metabolism seems very attractive.  相似文献   

15.
The objective of this work was to summarise and evaluate the evidence showing that physical activity is a protector factor as regards falls in older people. Relevant studies were identified through a systematic search in the MEDLINE and Cochrane Library, under the keywords of accidental fall/numerical data and risk factors, and with the bibliographies of retrieved papers. The combined odds ratio (OR) [95% confidence interval] for physical activity was 0.75 [0.64, 0.88] with moderate heterogeneity (I 2?=?33%). For fall injury, it was 0.59 [0.47, 0.74] and, for falls in general, it rose to 0.94 [0.76, 1.17] with nil heterogeneity. The combined OR for sedentary factors was 1.14 [1.10, 1.82] with moderate heterogeneity (I 2?=?36%). Regular physical activity in daily life yields significant reduction in falls in older people, especially falls with injuries.  相似文献   

16.
In most physiologic systems, there is considerable evidence that the normal aging processes do not result in significant impairment or dysfunction in the absence of pathology and under resting conditions. However, in response to a stress, the age-related reduction in physiologic reserves causes a loss of regulatory or homeostatic balance. This happens before an individual notices that something is wrong. An additional consequence of age-related changes is an increased perception of effort associated with submaximal work. Thus, a vicious cycle is set up, leading to decreasing exercise capacity, resulting in an elevated perception of effort, subsequently causing avoidance of activity, and finally feeding back to exacerbation of the age-related declines secondary to disuse. Sedentary behavior is an important risk factor for chronic disease morbidity and mortality in aging. However, there is a limited amount of information on the type and amount of activity needed to promote optimal health and function in older people [19]. The purpose of this review is to discuss the important role of exercise training as a primary prevention tool to hypertension. In addition, this review will address the topic of the recommended amount of physical activity required for health promotion along with the current exercise guidelines.  相似文献   

17.
Recent studies have provided partial insight into mechanisms underlying age-related declines in brain function. However, precisely where in the brain these changes occur is not entirely clear. A new report suggests that the hippocampal dentate gyrus may be the earliest locus of age-related memory decline.  相似文献   

18.
The article reports on a multilevel analysis conducted to examine change in neighborhood walking activity over a 12-month period in a community-based sample of 28 neighborhoods of 303 older adults age 65 and over. The study employed a multilevel (residents nested within neighborhoods) and longitudinal (4 repeated measures over 1 year) design and a multilevel analysis of change and predictors of change in neighborhood walking activity. Results indicated a significant neighborhood effect, with neighborhood-level walking characterized by a downward trajectory over time. Inclusion of baseline variables using selected perceived neighborhood-level social- and physical-environment measures indicated that neighborhoods with safe walking environments and access to physical activity facilities had lower rates of decline in walking activity. The findings provide preliminary evidence of neighborhood-level change and predictors of change in walking activity in older adults. They also suggest the importance of analyzing change in physical activity in older adults from a multilevel or macrolevel framework.  相似文献   

19.
Grounded in ecological theory, this study examines the association among participation in regular vigorous exercise and social status, aspects of prominent life settings, interactions between life settings, and more proximal individual resources and processes using data from the National Survey of Midlife Development in the United States (N = 3,032). Among women, a higher level of earnings was associated with more vigorous exercise, yet those women with more education had a steeper decline in exercise across adulthood. Among men, those with the lowest level of education had the steepest decline in physical activity across adulthood, and earnings did not affect exercise patterns. Less participation in vigorous exercise among blacks, in contrast to nonblacks, was explained by their tendency to live in less safe neighborhoods and having more functional health problems. Finally, contextual factors from multiple domains were independently associated with participation in regular exercise. Consistent with ecological theory, these results suggest that interventions to promote exercise habits among adults need to consider the independent and interactive effects of multiple contextual factors.  相似文献   

20.
This article contains a brief synopsis on nonpathological aspects of the neuropsychology of aging and cognitive health. In nonpathological aging, normal subtle decline occurs in a number of cognitive domains such as executive functioning, speed of processing, memory, language, and psychomotor ability; however, some domains of cognitive functioning appear to increase with age, such as vocabulary and crystallized intelligence. In the neuropsychology and the cognitive aging literatures, several hypotheses for such age-related declines are proposed, including the diminished speed-of-processing hypothesis, the common cause hypothesis, and the frontal aging hypothesis. As these age-related changes diminish cognitive reserve, the decline in the related cognitive domains emerges. Ways to protect and improve cognitive health are suggested to encourage positive neuroplasticity and discourage negative neuroplasticity. Implications for nursing practice are provided.  相似文献   

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