Correlates of physical activity in chronic obstructive pulmonary disease.

BACKGROUND: Physical activity is a key dimension of functional status in people with chronic obstructive pulmonary disease (COPD), and the central target of interventions in this group. OBJECTIVES: To determine the relationships among functional performance measured as physical activity, functional capacity, symptom experiences, and health-related quality of life in people with COPD. METHOD: Cross-sectional, descriptive study. Convenience sample of 63 outpatients with COPD studied prior to entry into a pulmonary rehabilitation program. RESULTS: Daily physical activity, as measured by an accelerometer, was strongly associated with maximal distance walked during a 6-minute walk test (r = .60, p < .00), level of airway obstruction (r = .37, p < .01), walking self-efficacy (r = .27, p < .05), and physical health status (r = .40, p < .01). Physical activity was not correlated with self-report of functional status. The only predictor of physical activity was the 6-minute walk test. CONCLUSIONS: Accelerometer measurement of functional performance was most significantly related to walking abilities. This methodology represents a novel approach to measuring an important dimension of functional status not previously well quantified.

Economic evaluation of a community based exercise programme to prevent falls.

OBJECTIVE: To assess the incremental costs and cost effectiveness of implementing a home based muscle strengthening and balance retraining programme that reduced falls and injuries in older women. DESIGN: An economic evaluation carried out within a randomised controlled trial with two years of follow up. Participants were individually prescribed an exercise programme (exercise group, n=116) or received usual care and social visits (control group, n=117). SETTING: 17 general practices in Dunedin, New Zealand. PARTICIPANTS: Women aged 80 years and older living in the community and invited by their general practitioner to take part. MAIN OUTCOME MEASURES: Number of falls and injuries related to falls, costs of implementing the intervention, healthcare service costs resulting from falls and total healthcare service costs during the trial. Cost effectiveness was measured as the incremental cost of implementing the exercise programme per fall event prevented. MAIN RESULTS: 27% of total hospital costs during the trial were related to falls. However, there were no significant differences in health service costs between the two groups. Implementing the exercise programme for one and two years respectively cost $314 and $265 (1995 New Zealand dollars) per fall prevented, and $457 and $426 per fall resulting in a moderate or serious injury prevented. CONCLUSIONS: The costs resulting from falls make up a substantial proportion of the hospital costs for older people. Despite a reduction in falls as a result of this home exercise programme there was no significant reduction in healthcare costs. However, the results reported will provide information on the cost effectiveness of the programme for those making decisions on falls prevention strategies.

Practical implementation of an exercise-based falls prevention programme.

Muscle weakness and impaired balance are risk factors underlying many falls and fall injuries experienced by older people. Fall prevention strategies have included exercise programmes that lower the risk of falling by improving strength and balance. We have developed an individually tailored, home-based, strength and balance retraining programme, which has proven successful in reducing falls and moderate fall injuries in people aged 80 years and older. Here we describe a simple assessment of strength and balance and the content and delivery of a falls prevention exercise programme.

The public health perspective in health promotion and disability prevention for older adults: the role of the Centers for Disease Control and Prevention.

As the United States federal public health agency, the role of the Centers for Disease Control and Prevention (CDC) in health promotion and disability prevention with older adults encompasses research, surveillance and program activities in aging. This article characterizes the objectives and context of prevention in later life and summarizes CDCs functions, collaborative partnerships with public health agencies and other organizations, and range of activities in older adult health. As a major focus of these efforts, chronic disease risk reduction is examined through CDC's efforts in the area of physical activity; a longitudinal investigation of osteoarthritis in an older biracial rural population; and chronic illness self-management programs as a prototype for secondary prevention. Other CDC activities highlighted include addressing the burden of vaccine-preventable diseases through CDC-funded programs to improve immunization coverage in older adults, and falls prevention interventions and resources. Future directions in aging at CDC are also outlined.

Effectiveness of physician-based assessment and counseling for exercise in a staff model HMO.

BACKGROUND: Few primary care physicians routinely counsel for exercise, despite the benefits of physical activity and the high prevalence of inactivity. The objective of this study is to assess the effectiveness of Physician-Based Assessment and Counseling for Exercise (PACE), a brief, behavior-based tool for primary care providers counseling healthy adults. METHODS: This study is a randomized controlled trial of 812 patients age 30 years or older registered for well visits at 32 primary care physician offices at a staff model health maintenance organization. Intervention physicians were trained to deliver PACE exercise counseling protocols at the index visit, and one reminder telephone call occurred at 1 month. An enhanced intervention group received additional activity reminders. RESULTS: At the 6-month follow-up, the control group did not differ significantly from the intervention group for energy expended (2,048 kcal/week versus 2,108 kcal/ week, P = 0.77), time spent in walking or other moderate to vigorous activities (202 min/week versus 187 min/ week, P = 0.99), mental health, physical function, or behaviors previously shown to predict activity change. Among the intervention patients, the stages-of-change score for Contemplators increased significantly compared with controls (P = 0.03), but without a significant change in energy expended. Baseline levels of physical activity counseling were high (50%), as were baseline patient physical activity levels (61% exercised at least three times a week). CONCLUSIONS: These results suggest that a one-time PACE counseling session with minimal reinforcement, in a setting with high baseline levels of activity, does not further increase activity. The finding that Contemplators advanced in stage of behavior change suggests that further studies are needed to examine long-term, repeated counseling interventions.

Quantitating physical activity in COPD using a triaxial accelerometer.

STUDY OBJECTIVE: To determine the reliability, validity, and stability of a triaxial accelerometer for walking and daily activity measurement in a COPD sample. DESIGN: Cross-sectional, correlational, descriptive design. SETTING: Outpatient pulmonary rehabilitation program in a university-affiliated Veterans Affairs medical center. PARTICIPANTS: Forty-seven outpatients (44 men and 3 women) with stable COPD (FEV(1), 37% predicted; SD, 16%) prior to entry into a pulmonary rehabilitation program. MEASUREMENTS AND RESULTS: Test-retest reliability of a triaxial movement sensor (Tritrac R3D Research Ergometer; Professional Products; Madison, WI) was evaluated in 35 of the 47 subjects during three standardized 6-min walks (intraclass correlation coefficient [rICC] = 0.84). Pearson correlations evaluated accelerometer concurrent validity as a measure of walking (in vector magnitude units), compared to walking distance in all 47 subjects during three sequential 6-min walks (0. 84, 0.85, and 0.95, respectively; p < 0.001). The validity of the accelerometer as a measure of daily activity over 3 full days at home was evaluated in all subjects using Pearson correlations with other indicators of functional capacity. The accelerometer correlated with exercise capacity (maximal 6-min walk, r = 0.74; p < 0.001); level of obstructive disease (FEV(1) percent predicted, r = 0.62; p < 0.001); dyspnea (Functional Status and Dyspnea Questionnaire, dyspnea over the past 30 days, r = - 0.29; p < 0.05); and activity self-efficacy (Activity Self-Efficacy Questionnaire, r = 0.43; p < 0.01); but not with self-report of daily activity (Modified Activity Recall Questionnaire, r = 0.14; not significant). Stability of the accelerometer to measure 3 full days of activity at home was determined by an rICC of 0.69. CONCLUSIONS: This study provides preliminary data suggesting that a triaxial movement sensor is a reliable, valid, and stable measure of walking and daily physical activity in COPD patients. It has the potential to provide more precise measurement of everyday physical functioning in this population than self-report measures currently in use, and measures an important dimension of functional status not previously well-described.

Factors that modify the association between knee pain and mobility limitation in older women: the Women's Health and Aging Study.

OBJECTIVE: To investigate the influence of pain severity, knee extensor muscle weakness, obesity, depression, and activity on the association between recent knee pain and limitation of usual and fast paced walking, and ability to rise from a chair. METHODS: A cross sectional analysis of 769 older women (mean age 77.8, range 65-101) with physical disability, but no severe cognitive impairment. Severity of knee pain in the past month was classified as none, moderate, or severe. Mobility was measured using timed performance tests. RESULTS: The prevalence of recent knee pain was 53% (408/769). One third of the women with pain reported it to be severe. In general, knee pain was only significantly associated with limited mobility if severe. Obesity, activity and, to a lesser extent, depression intensified the effects of pain. Knee extensor weakness did not. Obesity was a distinctive risk factor in that it substantially increased the risk of mobility limitation, but only in women with pain. In women who had severe pain, activity (walking more than three city blocks in the past week) increased the risk of walking disability more than inactivity. Depression had a minor, but statistically significant effect on walking ability, but not the ability to rise from a chair. CONCLUSION: In older women with recent knee pain, a high pain severity score, obesity, and activity are important factors that increase the risk of mobility limitation.

Falls prevention over 2 years: a randomized controlled trial in women 80 years and older.

BACKGROUND: after 1 year, a home-based programme of strength and balance retraining exercises was effective in reducing falls and injuries in women aged 80 years and older. The exercise programme had been individually prescribed by a physiotherapist during the first 2 months of a randomized controlled trial. OBJECTIVE: we aimed to assess the effectiveness of the programme over 2 years. SUBJECTS: women from both the control group and the exercise group completing a 1-year trial (213 out of the original 233) were invited to continue for a further year. METHODS: falls and compliance to the exercise programme were monitored for 2 years. RESULTS: 81 (74%) in the control group and 71 (69%) in the exercise group agreed to continue in the study. After 2 years, the rate of falls remained significantly lower in the exercise group than in the control group. The relative hazard for all falls for the exercise group was 0.69 (95% confidence interval 0.49-0.97). The relative hazard for a fall resulting in a moderate or severe injury was 0.63 (95% confidence interval 0.42-0.95). Those complying with the exercise programme at 2 years had a higher level of physical activity at baseline, were more likely to have reported falling in the year before the study and had remained more confident in the first year about not falling compared with the rest of the exercise group. CONCLUSIONS: falls and injuries can be reduced by an individually tailored exercise programme in the home. For those who keep exercising, the benefit continues over a 2-year period.

Psychotropic medication withdrawal and a home-based exercise program to prevent falls: a randomized, controlled trial.

OBJECTIVE: To assess the effectiveness of psychotropic medication withdrawal and a home-based exercise program in reducing falls in older people. DESIGN: A randomized controlled trial with a two by two factorial design. SETTING: Seventeen general practices in Dunedin, New Zealand. PARTICIPANTS: Women and men aged 65 years registered with a general practitioner and currently taking psychotropic medication (n = 93). INTERVENTIONS: Two interventions: (1) gradual withdrawal of psychotropic medication versus continuing to take psychotropic medication (double blind) and (2) a home-based exercise program versus no exercise program (single blind). MEASUREMENTS: Number of falls and falls risk during 44 weeks of follow-up. Analysis was on an intent to treat basis. RESULTS: After 44 weeks, the relative hazard for falls in the medication withdrawal group compared with the group taking their original medication was .34 (95% CI, .16-.74). The risk of falling for the exercise program group compared with those not receiving the exercise program was not significantly reduced. CONCLUSIONS: Withdrawal of psychotropic medication significantly reduced the risk of falling, but permanent withdrawal is very difficult to achieve.

Changing physician practice of physical activity counseling.

We conducted a prospective controlled trial to determine whether an educational intervention could improve resident physician self-efficacy and counseling behaviors for physical activity and increase their patients' reported activity levels. Forty-eight internal medicine residents who practiced at a Department of Veterans Affairs hospital received either two workshops on physical activity counseling or no intervention. All residents completed questionnaires before and 3 months after the workshops. The 21 intervention physicians reported increased self-efficacy for counseling and increased frequency of counseling compared with the 27 control physicians. Approximately 10 patients of each resident were included in the study and surveyed before and 6 months after the intervention. Of 560 patients, 465 (83%) returned both questionnaires. Following the intervention, there were no significant differences between patients of intervention and control physicians on any outcome measures. We conclude that educational interventions can improve physicians' reported self-efficacy of physical activity counseling but may not increase patient physical activity levels. Alternative approaches that emphasize overcoming the substantial barriers to exercise in chronically ill outpatients clearly will be important for facilitating changes in physical activity.

Exercise: effects on physical functional performance in independent older adults.

BACKGROUND: Age-related loss in physiologic capacities contributes to the decline in physical function in the elderly population. Despite the beneficial effects of exercise interventions on maximal physiologic capacity measures, the functional benefits have not been shown in independently living older adults. The objective of this study was to evaluate exercise in independent older adults for significant and meaningful improvements in physical function, not detected by commonly used measures of physical function. METHODS: In a randomized controlled study, 49 independently living men and women were assigned to either a nonexercise control group (Control; n = 26) or an exercise training group (Exercise; n = 23). Participants (age = 76+/-4) in good general health were recruited from retirement communities or apartments. The combined endurance and strength training was performed at 75% to 80% intensity; the groups met 3 times/week for 6 months of supervised sessions. Outcome measures included physical capacity, health status, and physical function using a newly developed performance test--the Continuous Scale-Physical Functional Performance test (CS-PFP). RESULTS: Compared to the Control group, the Exercise group showed significant increases in maximal oxygen consumption (11%) and muscle strength (33%). No significant differences were found between groups for changes in the Sickness Impact Profile, SF-36 scales, or the 6-minute walk. However, the CS-PFP score improved significantly in the Exercise group (14%, effect size 0.80). CONCLUSIONS: Independent older adults gain meaningful functional benefits from several months of exercise training. The public health importance of physical activity may relate not just to its role in preventing decline, but also to its role in enhancing physical function.

Physical activity interventions targeting older adults. A critical review and recommendations.

BACKGROUND: Although many of the chronic conditions plaguing older populations are preventable through appropriate lifestyle interventions such as regular physical activity, persons in this age group represent the most sedentary segment of the adult population. The purpose of the current paper was to provide a critical selected review of the scientific literature focusing on interventions to promote physical activity among older adults. METHODS: Comprehensive computerized searches of the recent English language literature aimed at physical activity intervention in adults aged 50 years and older, supplemented with visual scans of several journal on aging, were undertaken. Articles were considered to be relevant for the current review if they were community-based, employed a randomized design or a quasi-experimental design with an appropriate comparison group, and included information on intervention participation rates, pre- and post-intervention physical activity levels, and/or pre/post changes in relevant physical performance measures. RESULTS: Twenty-nine studies were identified that fit the stated criteria. Among the strengths of the studies reviewed were reasonable physical activity participation rates and relatively long study durations. Among the weaknesses of the literature reviewed were the relative lack of specific behavioral or program-based strategies aimed at promoting physical activity participation, as well as the dearth of studies aimed at replication, generalizability of interventions to important subgroups, implementation, and cost-effectiveness evaluation. CONCLUSIONS: Recommendations for future scientific endeavors targeting older adults are discussed.

Predicting hospitalization and functional decline in older health plan enrollees: are administrative data as accurate as self-report?

OBJECTIVE: To compare the predictive accuracy of two validated indices, one that uses self-reported variables and a second that uses variables derived from administrative data sources, to predict future hospitalization. To compare the predictive accuracy of these same two indices for predicting future functional decline. DESIGN: A longitudinal cohort study with 4 years of follow-up. SETTING: A large staff model HMO in western Washington State. PARTICIPANTS: HMO Enrollees 65 years and older (n = 2174) selected at random to participate in a health promotion trial and who completed a baseline questionnaire. MEASUREMENT: Predicted probabilities from the two indices were determined for study participants for each of two outcomes: hospitalization two or more times in 4 years and functional decline in 4 years, measured by Restricted Activity Days. The two indices included similar demographic characteristics, diagnoses, and utilization predictors. The probabilities from each index were entered into a Receiver Operating Characteristic (ROC) curve program to obtain the Area Under the Curve (AUC) for comparison of predictive accuracy. RESULTS: For hospitalization, the AUC of the self-report and administrative indices were .696 and .694, respectively (difference between curves, P = .828). For functional decline, the AUC of the two indices were .714 and .691, respectively (difference between curves, P = .144). CONCLUSIONS: Compared with a self-report index, the administrative index affords wider population coverage, freedom from nonresponse bias, lower cost, and similar predictive accuracy. A screening strategy utilizing administrative data sources may thus prove more valuable for identifying high risk older health plan enrollees for population-based interventions designed to improve their health status.

Implementation and effectiveness of a community-based health promotion program for older adults.

BACKGROUND: Because preventing functional decline in older adults is a national priority and senior centers have been identified as potentially important venues for health-promotion activities, a trial of a multicomponent disability prevention program was conducted at a senior center. METHODS: One hundred older adults were recruited for a 6-month randomized clinical trial. All members of the experimental group received an exercise intervention, nutrition counseling, and a home safety assessment. Smoking and alcohol interventions were delivered to at-risk subjects. Outcome variables included the Medical Outcomes Study Short Form (SF-36) health survey, the CES-Depression scale, bed days, and restricted-activity days. RESULTS: A single study announcement resulted in a response sufficient to recruit 100 subjects. The exercise program was well received: 85% of intervention subjects completed the 6-month program and adherence was excellent, with over 90% attendance at exercise classes. After 6 months the intervention group had significantly better scores on 7 of 8 SF-36 subscales and fewer depressive symptoms than controls. CONCLUSIONS: Senior centers may be excellent sites for community-based health promotion interventions: participation and adherence rates may be acceptable, interventions can be designed that are feasible in this setting, and these interventions appear to affect health status positively. The study program improved physical and psychosocial functioning and is a promising model for preventing functional decline through activities based at senior centers.

Exercise and activity level in Alzheimer's disease: a potential treatment focus.

This article provides information on the baseline health and physical function of 30 individuals with Alzheimer's disease (AD); describes a community-based program designed to increase balance, flexibility, strength, and endurance in these persons by the training of caregivers to facilitate and supervise exercise activity; and documents the adherence of these subjects and their caregivers to this intervention. Subjects were recruited from an ongoing, community-based Alzheimer's Disease Patient Registry, and met NINCDS-ADRDA criteria for probable or possible AD. Caregivers were family members living with the demented individuals in the community. Physical performance was measured using walking speed, functional reach, and standing balance. Health status was measured with the Medical Outcomes Study Short Form, the Sickness Impact Profile, and caregiver reports of subject's restricted activity days, bed disability days, falls, and exercise participation. Baseline data indicated that persons with AD were impaired on measures of physical performance and function, compared to published data on nondemented older adults. During a 12-wk treatment period, caregivers were taught to guide their demented charges in an individualized program of endurance activities (primarily walking), strength training, and balance and flexibility exercises. Adherence data indicated that 100% of the subjects were compliant with some exercise recommendations, and one-third completed all assigned exercises during the training period. Caregivers were able to learn and direct subjects during scheduled exercise activities. These findings indicate that the integration of exercise training into the care of persons with AD is both needed and feasible. Further research is currently underway to determine the efficacy of this approach for reducing additional physical disability in these individuals.

Preserving mobility in older adults.

Age-related loss of strength contributes to impaired mobility and increases the risk of falls. Recent research has focused on 2 approaches to preventing age-related loss of strength--promoting physical activity and exercise (especially strength training) and using trophic factors to enhance muscle performance. Epidemiologic evidence strongly supports a role of regular physical activity in successful aging by preserving muscle performance, promoting mobility, and reducing fall risk. Randomized controlled trials provide convincing evidence that strength and endurance training improve muscle performance in older adults. Evidence is rapidly accumulating from randomized trials that endurance, strength, and balance training promote mobility and reduce fall risk, though exercise effects differ according to the type of exercise, details of the exercise program, and the target group of older adults. Because lifetime regular physical activity is recommended for all older adults, a reasonable strategy (especially for weak adults) is an activity program that includes strength training. In contrast, insufficient evidence exists to recommend the long-term use of trophic factors to preserve muscular performance. An intervention that merits additional study is avoiding the use of psychoactive drugs because drugs like benzodiazepines appear to be risk factors for inactivity and may have unrecognized direct effects on muscular performance. Because chronic illness is a risk factor for inactivity and disuse muscle atrophy, randomized trials comparing strength training with other interventions would be useful in understanding whether strength training has advantages in preserving muscle performance and improving health-related quality of life in a variety of chronic illnesses such as depressive illness.

Gender, self-reported depressive symptoms, and sleep disturbance among older community-dwelling persons. FICSIT group. Frailty and Injuries: Cooperative Studies of Intervention Techniques.

The purposes of this report are: (1) to investigate the association between sleep disturbances and depressive symptomatology in older adults; (2) to evaluate the degree to which gender serves to mediate this relationship; and (3) to determine whether several predefined covariates help to explain the association between sleep disturbance and depressive symptoms. This is a retrospective and cross-sectional analysis of baseline data from 485 elderly adults enrolled in three of the eight clinical sites participating in the Frailty and Injuries: Cooperative Studies of Intervention Techniques (FICSIT) trials. FICSIT was a linked series of randomized clinical trials which evaluated the impact of various exercise interventions on several measures of frailty in older adults. Women reported more depressive symptoms and more sleep disturbances than men. Sleep disturbances were independently associated with depressive symptoms, bodily pain, a history of falling, limited education, being married, and being female. Gender interactions suggest that, although women reported more depressive symptoms and more chronic health conditions than men, both may be more important predictors of sleep disturbance in men. By contrast, being married may be more predictive in women. Finally, the data suggest a stronger relationship between sleep disturbance and depressive symptoms in men than in women.

Randomised controlled trial of a general practice programme of home based exercise to prevent falls in elderly women.

OBJECTIVE: To assess the effectiveness of a home exercise programme of strength and balance retraining exercises in reducing falls and injuries in elderly women. DESIGN: Randomised controlled trial of an individually tailored programme of physical therapy in the home (exercise group, n = 116) compared with the usual care and an equal number of social visits (control group, n = 117). SETTING: 17 general practices in Dunedin, New Zealand. SUBJECTS: Women aged 80 years and older living in the community and registered with a general practice in Dunedin. MAIN OUTCOME MEASURES: Number of falls and injuries related to falls and time between falls during one year of follow up; changes in muscle strength and balance measures after six months. RESULTS: After one year there were 152 falls in the control group and 88 falls in the exercise group. The mean (SD) rate of falls was lower in the exercise than the control group (0.87 (1.29) v 1.34 (1.93) falls per year respectively; difference 0.47; 95% confidence interval 0.04 to 0.90). The relative hazard for the first four falls in the exercise group compared with the control group was 0.68 (0.52 to 0.90). The relative hazard for a first fall with injury in the exercise group compared with the control group was 0.61 (0.39 to 0.97). After six months, balance had improved in the exercise group (difference between groups in change in balance score 0.43 (0.21 to 0.65). CONCLUSIONS: An individual programme of strength and balance retraining exercises improved physical function and was effective in reducing falls and injuries in women 80 years and older.

Potential applications of GH secretagogs in the evaluation and treatment of the age-related decline in growth hormone secretion.

The two classes of GH secretagogs--GH-releasing hormone (GHRH) and the GH-releasing peptides and their analogs (GHRP's)--retain their ability to endogenous GH secretion in healthy and frail elderly subjects. They have very limited utility in assessment of the state of the GH/IGF-I axis except to confirm an intact pituitary, but they are attractive potential alternatives to GH as therapeutic agents. There is wide interest in the possibility that elevating GH and IGF-I might increase muscle mass, physical strength and performance, and possible sleep and cognition in aging. The GH secretagogs, like GH, can produce a sustained stimulation of this axis; in contrast to GH, they preserve feedback regulation at the pituitary level and stimulate a near-physiologic pulsatile pattern of GH release. GHRP's and their nonpeptide analogs are also active when given orally, a significant practical advantage. Short-term treatment studies have shown that GHRH and the GHRP's can enhance GH secretion and elevate IGF-I and IGFBP-3 levels; that GHRH may promote sleep; and that these agents are generally well tolerated. Longer-term studies assessing effects upon body composition and physical and psychological function are underway.

The effect of strength and endurance training on gait, balance, fall risk, and health services use in community-living older adults.

BACKGROUND: The study tested the effect of strength and endurance training on gait, balance, physical health status, fall risk, and health services use in older adults. METHODS: The study was a single-blinded, randomized controlled trial with intention-to-treat analysis. Adults (n = 105) age 68-85 with at least mild deficits in strength and balance were selected from a random sample of enrollees in a health maintenance organization. The intervention was supervised exercise (1-h sessions, three per week, for 24-26 weeks), followed by self-supervised exercise. Exercise groups included strength training using weight machines (n = 25), endurance training using bicycles (n = 25), and strength and endurance training (n = 25). Study outcomes included gait tests, balance tests, physical health status measures, self-reported falls (up to 25 months of follow-up), and inpatient and outpatient use and costs. RESULTS: There were no effects of exercise on gait, balance, or physical health status. Exercise had a protective effect on risk of falling (relative hazard = .53, 95% CI = .30-.91). Between 7 and 18 months after randomization, control subjects had more outpatient clinic visits (p < .06) and were more likely to sustain hospital costs over $5000 (p < .05). CONCLUSIONS: Exercise may have beneficial effects on fall rates and health care use in some subgroups of older adults. In community-living adults with mainly mild impairments in gait, balance, and physical health status, short-term exercise may not have a restorative effect on these impairments.