A physical fitness model of older adults

Physical fitness for young people is viewed as a multidimensional construct, in that it consists of specific components such as strength, mobility, balance, flexibility, and stamina. This study examined whether this structure underlying physical fitness is also relevant to older adults. A 10-item performance test, which was assumed to assess six components of physical fitness, was administered to 69 healthy volunteers ranging in age from 61 to 83 years. A covariance structure model was applied to the test data: the second-order factor was Physical Fitness, and the first-order factors were Strength, Walking, Balance, Flexibility, Stamina, and Manual Speed which were assumed to be measured based on the ten observed variables. Goodness-of-fit index (GFI) of the model was acceptable (GFI = 0.93). While four factors relating to basic motor performances (Strength, Walking, Balance, and Manual Speed) had loadings more than 0.62 to Physical Fitness, Flexibility and Stamina had less than 0.35. It was suggested for elderly people that strength, mobility, balance, and speed components of physical fitness were highly correlated and explainable by a single factor, while flexibility and cardiorespiratory endurance were to be measured by use of specific measures.     

Physical fitness and psychological benefits of strength training in community dwelling older adults

Previous studies concerning psychological benefits of exercise among the elderly has focused predominantly on the effects of aerobic exercise. In the present study, psychological and behavioral adaptations in response to 12-weeks of strength training were examined in medically healthy but sedentary 42 older adults (mean age = 68 years). The purpose of this study was to evaluate the effects of high and low intensity resistance training intensity on a) muscular fitness, b) psychological affect, and c) neurocognitive functioning. Subjects were randomly assigned to high intensity/low volume (EXH: 2 sets of 8 to 10 repetitions for 75 to 85% of 1 RM), low intensity/high volume (EXL: 2 sets of 14 to 16 repetitions for 55 to 65% of 1 RM), or no exercise control programs. Prior to and following the 12-week program, subjects underwent comprehensive physiological and psychological evaluations. Physiological assessment included measurements of blood pressure, heart rate, arm and leg muscle strength, body composition, and oxygen consumption (VO2max). Psychological measures included evaluations of mood, anxiety, and physical self-efficacy as well as cognitive functioning. The results of this study indicated that both high and low intensity strength programs were associated with marked improvements in physiological fitness and psychological functioning. Specifically, subjects in the strength training programs increased overall muscle strength by 38.6% and reduced percent body fat by 3.0%. Favorable psychological changes in the strength-trained subjects included improvements in positive and negative mood, trait anxiety, and perceived confidence for physical capability. The treatment effects of neurocognitive functioning were not significant. In summary, this study demonstrated that participation in 12-weeks of high or low intensity strength training can improve overall physical fitness, mood, and physical self-efficacy in older adults while cognitive functioning remains constant.     

Cardiovascular fitness, physical activity and selected coronary heart disease risk factors in adults

This article considers the mechanism for construction of movements in biological systems as a means of reducing excess degrees of freedom of a motor organ. It is suggested that each type of excess of degrees of freedom is reduced by one of the hierarchically coordinated systems of motor control. Detailed consideration is given to mechanisms for reducing the dynamic excess of a motor organ, the kinematic excess associated with polyarticular motor organs, and the kinematic excess of the desired trajectory. A functional scheme is developed for a motor control system which reduces these excess degrees of freedom, and the control processes for various types of movement were studied by computer modeling.     

Physical activity efficacy and effectiveness among older adults and minorities

The objective of this study was to consider efficacy and effectiveness of physical activity for the prevention and management of NIDDM among minorities and older adults of the U.S. Relevant population trends and projections are discussed, followed by a review of the efficacy of physical activity based on theoretical, prospective cohort, and intervention studies. With few empirical studies available, the assessment of effectiveness is largely theoretical and focuses on potentially important issues for future studies among older adults and minorities. Efficacy studies have shown that moderate-intensity physical activity is associated with a one- to two-thirds lower incidence of NIDDM over 4-14 years and 15-20% lower glycosylated hemoglobin over 3-4 months among people with NIDDM. With physical inactivity prevalence at 60-70%, much work remains to be done to improve physical activity effectiveness. In the most vulnerable populations, physician referral and community involvement structured around stage of change and self-efficacy theories are suggested as the most promising approaches to promoting physical activity adoption and maintenance. Effectiveness or demonstration studies that test and build on stage of change, self-efficacy, and other concepts of physical activity promotion and outcomes would likely prove to be highly valuable investments for public health.     

Long-term follow-up of physical activity behavior in older adults.

Objective: To examine the contribution of social-cognitive factors (self-efficacy and affect) in predicting long-term physical activity in a sample of older adults (N = 174). Design: A prospective design assessed physical activity and psychosocial variables at 2 and 5 years following a 6-month randomized, controlled exercise trial. Main Outcome Measures: The primary outcome variable was self-reported physical activity, with previous behavior, self-efficacy, and affect assessed as determinants of physical activity. Results: Covariance modeling analyses indicated that physical activity at Year 2 was the strongest predictor of physical activity at 5-year follow-up. Both self-efficacy and affect at Year 2 were also associated with physical activity at Year 5, as was original treatment condition. Variables accounted for 35% of the variance in Year 5 activity. Conclusion: Older adults with higher levels of physical activity, more positive affect, and higher self-efficacy at Year 2 were more likely to continue to be active at Year 5. This study is one of the longest follow-ups of exercise behavior in older adults and has implications for structuring environments to maximize the maintenance of physical activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cardiorespiratory fitness, hippocampal volume, and frequency of forgetting in older adults.

Objective: The purpose of this study was to extend our earlier work to determine the extent to which cardiorespiratory fitness is associated with the frequency of memory problems via its effects on the hippocampus and spatial working memory. We hypothesized that age, sex, education, body composition, and physical activity were direct determinants of fitness, which, in turn, influenced frequency of forgetting indirectly through hippocampal volume and spatial working memory. Method: We conducted assessments of demographic characteristics, Body Mass Index (BMI), physical activity, cardiorespiratory fitness, hippocampal volume, spatial working memory, and frequency of forgetting in 158 older adults (M age = 66.49). Path analyses within a covariance modeling framework were used to examine relationships among these constructs. Results: Sex, age, BMI, and education were all significant determinants of cardiorespiratory fitness. The hypothesized path models for testing the effects of fitness on frequency of forgetting through hippocampal volume and accuracy and speed of spatial working memory all fit the data well. Conclusions: Our findings suggest that older adults with higher levels of fitness show greater preservation of hippocampal volume, which, in turn, is associated with more accurate and faster spatial memory and fewer episodes of forgetting. Given the proportion of older adults reporting memory problems, it is necessary to determine whether improvements in fitness brought about by physical activity interventions can result in subsequent attenuation of memory problems or potentially in improvements in memory. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Physical activity, physical fitness, and all-cause and cancer mortality: a prospective study of men and women

We studied physical fitness and physical activity in relation to all-cause and cancer mortality in a cohort of 7080 women and 25,341 men examined at the Cooper Clinic in Dallas, Texas, during 1970 to 1989. Physical fitness was assessed at baseline by a maximal treadmill exercise test, while physical activity was self-reported on the attendant health habits questionnaire. Both men and women averaged about 43 years of age at baseline (range, 20 to 88 years), and they were followed for approximately 8 years on average. Through the end of 1989, the women contributed 52,982 person-years of observation and incurred 89 deaths, including 44 deaths due to cancer. The men contributed 211,996 person-years and incurred 601 deaths, with 179 due to cancer. After adjustment for baseline differences in age, examination year, cigarette habit, chronic illnesses, and electrocardiogram abnormalities, we found a strong inverse association between risk of all-cause mortality and level of physical fitness in both men and women (P for trend < 0.001). Physically active men also were at lower risk of all-cause mortality than were sedentary ones (P for trend = 0.01). Among women, however, self-reported physical activity was not significantly related to risk of death from all causes. The risk of mortality from cancer declined sharply across increasing levels of fitness among men (P for trend < 0.001), whereas among women the gradient was suggestive but not significant (P for trend = 0.07). Physically active men also were at lower risk of death from cancer than were sedentary men (P for trend = 0.002), but among women physical activity was unrelated to cancer mortality.     

Telephone versus mail interventions for maintenance of physical activity in older adults.

Although telephones and the mail are often used to promote physical activity, their ability to produce long-term maintenance is unclear. In this study, 140 men and women aged 50–65 years received 1 year of telephone counseling aimed at the adoption of higher (i.e., more vigorous) versus lower intensity (i.e., moderate) exercise. After 1 year, participants were rerandomized to a 2nd year of contact via (a) telephone and mail or (b) predominantly mail. Participants who were prescribed higher intensity exercise and who predominantly received mail had better exercise adherence during the maintenance year than those who received telephone and mail. Both strategies were effective in promoting maintenance in the lower intensity condition. Results suggest that after successful adoption of physical activity with the help of telephone counseling, less intensive interventions are successful for physical activity maintenance in older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Physical inactivity in New Zealanders aged 60 years and older

AIMS: To determine the prevalence of physical inactivity among older New Zealanders (> or = 60 years) and to examine the patterns of physical inactivity by sex, age, residential and cognitive status. METHODS: Information on housework-related and leisure-time physical activities obtained from the 910 controls in the Auckland Hip Fracture Study, was used to determine the prevalence of inactivity. Direct standardisation was used to extrapolate the inactivity prevalence figures from the study population to the general Auckland population. Logistic regression analyses were undertaken to examine the patterns of physical inactivity by sex, age, residential and cognitive status. RESULTS: Of the study participants 48.7% did not undertake any leisure-time physical activities and 15.6% did not undertake any physical activity. Extrapolation of these data to the Auckland population indicated that 38.9% of older people do not participate in any leisure time activity and 6.1% do not partake in any physical activity. Non-participation in physical activities was shown to be greater for women (odds ratio = 1.92; 95% confidence interval: 0.98-4.07); those in the older age groups (> or = 90 years, 7.00; 1.88-45.60); those living in institutions (6.52; 4.01-10.64); and for those who were cognitively impaired (13.96; 7.06-28.92). CONCLUSION: Policies and programmes should focus on encouraging and supporting older people to become physically more active, by engaging in activities in which they enjoy participating; by educating older people as to the feasibility and benefits of physical activities, including maintenance of an independent active life; and by encouraging residents in institutions to continue their involvement in housework-related activities, such as gardening, home maintenance and general housework.     

Physical health impairment and depression among older adults

We studied the effect of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1), and interferon-gamma (IFN-gamma) on the function of thyroid cells and pituitary thyrotrophs. In FRTL-5 rat thyroid cells, both human and murine TNF-alpha inhibited basal and TSH-stimulated [125I]iodide transport. IL-1 shared this action with TNF-alpha, but was less potent. IL-1 and IFN-gamma did not cause a further reduction of TNF-alpha-induced inhibition of [125I]iodide transport. TNF-alpha, phorbol ester 12-myristate 13-acetate (PMA), and calcium ionophore (CI) A23817 all inhibited [125I]iodide transport, but high doses of PMA and CI also blocked the inhibitory action of TNF-alpha on [125I]iodide transport. Inhibition of protein kinase A and protein kinase C by H7 or HA inhibited TSH-stimulated iodide transport, but did not block the TNF-alpha action, suggesting that the mechanism of TNF-alpha action on thyroid cells is independent of protein kinase A and C. In pituitary cells, both human and murine TNF-alpha did not affect basal TSH secretion, but TNF-alpha reduced TRH-stimulated TSH secretion. This study provides further in vitro evidence that TNF-alpha inhibits the function of the hypothalamus-pituitary-thyroid axis acting directly on both the pituitary and thyroid glands.     

Association between aerobic fitness and visuospatial performance in healthy older adults.

Examined whether chronic physical exercise activity is associated with better neurocognitive performance in older adults. 105 men participated in 1 of 3 age groups (18–28, 35–45, and 60–73 yrs). For each age group, Ss were classified as high or low in fitness on the basis of self-reported activity levels and the results of a submaximal bicycle ergometer test. A comprehensive battery of neuropsychological tests was administered to each S, and older Ss scored significantly lower than the younger groups on most tests. Significant differences between high- and low-fit Ss were found only on tasks with heavy visuospatial demands, and these differences were most notable in the older adult group. These findings suggest that participation in aerobic exercise activity selectively preserves some cognitive functions that normally decline with age. The benefits of activity appear to be most evident on tasks that require visuospatial processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Six-month physical activity and fitness changes in Project Active, a randomized trial

PURPOSE: Project Active is a randomized clinical trial (N = 235) comparing a lifestyle physical activity program with a structured exercise program in changing physical activity (total energy expenditure [kcal.kg-1.d-1]) and cardiorespiratory fitness (VO2peak in mL.kg-1.min-1). METHODS: Sedentary but healthy adults (N = 235) aged 35-60 years received 6 months of intensive intervention. RESULTS: Analysis of covariance (ANCOVA), adjusting for baseline measure, age, gender, body mass index (BMI), cohort, and ethnicity, showed that at 6 months both lifestyle and structured groups significantly increased energy expenditure over baseline (P < 0.001). The mean increases +/- SE, 1.53 +/- 0.19 kcal.kg-1.d-1 for the lifestyle group and 1.34 +/- 0.20 kcal.kg-1 d-1 for the structured group, were not significantly different between groups (P = 0.49). For cardiorespiratory fitness, both groups had significant increases from baseline (P < 0.001). Mean increases +/- SE were 1.58 +/- 0.33 mL.kg-1.min-1 and 3.64 +/- 0.33 mL.kg-1.min-1 for the lifestyle and structured groups, respectively. This was significantly greater in the structured group (P < 0.001). We also studied changes in intensity of physical activity. Both groups significantly increased moderate intensity activity from baseline, but the increase was significantly greater in the lifestyle group than the structured group (P = 0.02). In contrast, the structured group increased its hard activity more than the lifestyle group, but the difference was not significantly different (P = 0.02). In contrast, the structured group increased its hard increased (P < 0.01) for both groups by 0.25 kcal.kg-1.d-1. CONCLUSION: Both intervention approaches are effective for increasing physical activity and fitness over a 6-month period in initially sedentary men and women.     

Everyday activity parameters and competence in older adults

Parameters of everyday activities in relation to cognitive, social, and emotional competence were examined in 2 studies. The parameters included frequency, difficulty, importance, intentions for future activities, changes in past activities, and ability of performance. The challenge hypothesis, in which performance of optional activities experienced as moderately difficult is associated with greatest well-being, was also tested. Two samples of older adults completed a life history interview and measures of psychological functioning. Parameters of activities necessary for maintaining an independent engaged lifestyle were measured by the Everyday Activities Questionnaire. In both studies, competence variables helped explain activity parameters independently of age and demographic variables. There was no support for the challenge hypothesis in either study.     

Associations between skeletal muscle properties, physical fitness, physical activity and coronary heart disease risk factors in men

High physical fitness and physical activity are associated with favourable lipid levels, especially a high level of high density lipoprotein cholesterol (HDL-C). A person's skeletal muscle properties, metabolism and percentage of different muscle fibres (ST-%), which may modify coronary heart disease (CHD) risk factors, such as serum insulin, obesity and serum sex hormones may also influence his fitness level and leisure-time physical activity. We studied the associations of physical fitness, physical activity and ST-% with serum lipids and lipoproteins in 72 healthy men. Their parameters were compared with those of 20 men with defined CHD. Significant interrelationships between ST-%, fitness and leisure-time physical activity index (LTPAI) were observed. Multiple regression analysis showed that ST-%, fitness and leisure-time physical activity explained about 32% of the variation in HDL-C in the healthy men. In healthy men ST-% correlated positively with fitness (r(s) = 0.62, P < 0.001) and with LTPAI (r(s) = 0.62, P < 0.001). Fitness level also correlated significantly with LTPAI (r(s) = 0.81, P < 0.001). Serum insulin showed negative associations with ST-% (r(s) = -0.63, P < 0.001) and fitness (r(s) = -0.54, P < 0.001) and LTPAI (r(s) = -0.62, P < 0.001). Free fraction of testosterone correlated negatively with serum HDL-C level (r(s) = -0.34, P < 0.01), with fitness (r(s) = -0.41, P < 0.001) and with LTPAI (r(s) = -0.54, P < 0.001). In sedentary men with the lowest fitness and physical activity the mean of ST-% (45%) was similar to that in CHD patients (44%). However, ST-% in men in the highest tertile of physical activity and fitness (68%) was significantly higher than in CHD patients and in men in the lowest tertile of physical activity and fitness. Skeletal muscle enzyme activity in lipid metabolism was significantly lower in both CHD patients and in sedentary and low-fit men than that in fitter and physically active men. The present data imply that skeletal muscle properties are important determinants of risk profiles, such as physical activity, fitness and serum lipid and lipoprotein patterns. Although fitness is a graded, independent predictor of mortality from CHD, a relatively high fitness level is not enough. This was clearly observed in the clustering analysis, in which the healthy men, according to their ST-%, fitness, leisure-time physical activity and serum sex hormone binding globulin (SHBG), fell into three natural groups: (i) Inactive men with lowest ST-% (mean 42%), lowest fitness (10.7 METs) and lowest HDL-C (1.36 mm/l); (ii) Fit men with high ST-% (66%), high fitness (14.5 METs) and moderately high HDL-C (1.54 mol/l); (iii) Active men with high ST-% (66%), highest fitness (14.9 METs) and highest serum HDL (1.83 mmol/l). The results support the idea that both fitness and physical activity give further protection against CHD by modifying risk factors. Our findings also suggest that skeletal muscle properties should be considered in the studies which assess CHD risk factors and their modifications especially in the field of health-related fitness.     

Physical fitness of Danish men and women aged 50 to 80 years

Maximal power in sustained work in originally randomly selected men and women, born in 1914, was studied five times between the ages of 50 and 80 years in a longitudinal design. Of the originally 514 men and 461 women in 1964 living in the Western suburbs of Copenhagen, 23 men and 18 women performed a bicycle test at age 50, 60, 70, 75 and 80. The mean annual decline in body mass adjusted maximal power in sustained work (W/kg) was 1.43% in the 18 men and 1.64% in the 23 women. Based on "cross-sectional" comparisons of all subjects tested at any age, the mean annual decline in men was 1.56%; in women the corresponding figure was 1.80%. When the results of the "longitudinal" and "cross-sectional" analyses were compared with each other, a rather similar picture of the age-related decline in maximal power was obtained, especially in women. In the longitudinal data only moderate (women) or zero (men) correlations were observed between the submaximal test results at the ages of 50 and 60 years and the maximal test results at higher ages. The physical work load at the age of 50 years had no significant correlation with maximal power at that age or thereafter. There were only minor changes in mean body height, body mass and BMI during the follow-up.     

Patient self-assessment of tibial plateau fractures in 40 older adults

The prevalence of refractory partial seizure Thai patients at Prasat Neurological Institute was retrospectively from patient charts from January 1995-December 1996 and further prospectively analysed. All epileptic patients were screened by direct questions regarding the anti-epileptic drugs (AEDs) regimen, the frequency, nature of seizure attacks and risk factors of seizure. The criteria of clinical refractory partial seizure was defined as partial seizure which cannot be controlled by a combination of at least two AEDs for four weeks. The results were 3,018 cases of total epileptic patients out of 300,008 visits. These were classified as 2,802 cases of generalized seizures (92.8%), 184 cases of partial seizures (6.1%), and 32 cases of unclassified seizures (1.1%). In the partial seizures group, the number of clinical refractory partial seizures was found to be 48 cases (26.1% of partial seizure). We found that the major risk factor of refractory partial seizures was lack of therapeutic AEDs blood level monitoring (64.5% of cases) and the other risk factors were lack of compliance, loss of follow-up but continued medication, concomitant medication, and improper drug storage. AEDs dosage was adjusted until the blood levels were in the therapeutic range, and correction of other risk factors and patient counseling was given. The number of true refractory partial seizures was reduced to 10 cases (5.4% of partial seizure). This procedure revealed that AED blood level monitoring and correction of other risk factors were essential in controlling seizure frequency. Thus, the prevalence of true refractory partial seizure in our study was 3.3 cases of refractory partial seizure per 1,000 cases of the seizure population. We recommend that AEDs blood level monitoring and exclusion of other risk factors should be added to the criteria for the definition of refractory partial seizures. This criteria should be applied when considering the use of new AEDs as an add-on therapy in refractory Thai patients.     

Relationships between physical exercise and cognitive abilities in older adults.

We investigated relationship between physical exercise and the cognitive abilities of older adults. We hypothesized that the performance of vigorous exercisers would be superior to that of sedentary individuals on measures of reasoning, working memory, and reaction time (RT). We gave a series of cognitive tasks to 62 older men and women who exercised vigorously and 62 sedentary men and women. Multivariate and univariate analyses of variance (ANOVAs), with age and education as covariates, indicated that the performance of the exercisers was significantly better on measures of reasoning, working memory, and RT. Between-group differences persisted when vocabulary, on which the performance of exercisers was superior, was used as third covariate. Subsequent analyses showed that neither self-rated health, medical conditions, nor medications contributed to the differences between exercise groups. Results suggest that the possible contribution of physical exercise to individual differences in cognition among older adults should be further investigated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)